Our final speaker today is Joanna Messer Kimmet, Director of Library Programs and Services at Cabrillo College. She has extensive experience in public and academic library consortium services, personal management, systems and metadata, instruction in both professional development and academic programs and user experience assessment in online and face-to-face environments. Joanna's recent work has focused on textbook affordability, controlled digital lending, instruction-centered management and responses to burnout through organizing efforts in libraries. She is active in ALA's core and ACRL divisions and is current chair for MOBAC's Administrative Council. Today, she will be speaking to us about controlled digital lending for equitable access and lessons learned from implementing CDL. Thank you so much for having me here today to talk about our control digital lending program at Cabrillo College. So control digital lending, how does this work? How do you make this happen for your library? What this presentation is, it's going to be a brief definition and an overview of control digital lending for those of you who may not have heard of this term before. A brief case study of our particular project, practical considerations for decisions about starting up your own CDL program and then some connections and resources for participants who are interested in CDL solutions for your libraries. So what this presentation is not, I am not a lawyer. I cannot give you legal advice about starting a CDL program. Also my library's context as a community college library, part of an overarching system in that way, is not going to be the same as your library's context. Though I do have a lot of experience in public libraries and my mother was a public library director in a small town in Illinois and I grew up around it, your context really is going to be very different from what we are able to do at Cabrillo. But there are a lot of similarities and a lot of partnerships that we can make together. I'm also not a guide to finding funding for your CDL project. I'm a guide to finding funding for mine most of the time. It's also not going to be an overview of current case law because there's a really big lawsuit that is currently pending. How many of you have heard of this? The Internet Archive lawsuit, yes. There have been some very recent developments and some final briefs were filed just over two weeks ago or just under two weeks ago in that case and a motion for summary judgment. Again, I am not a lawyer. I can't explain all of that to you nearly as elegantly as those who are and who are intimately involved in that process. So if you want to learn more, please by all means go out and do so. But I can't guide you through those intricacies. I can only talk about what we did and the standing that we had for our project. So a little bit more about me and about my library. I've been the director of library programs and services and administrative role at Cabrillo College since July of last year. I came from Cal State Dominguez Hills, Gotoros, where I was in the library faculty for four years that's in the South Bay area of Los Angeles and now I'm in the Monterey Bay area up here. So our library, these are some interior shots and exterior shots. Our library is sort of in the center of our campus in Aptos. It is two floors. Most of our materials and spaces are on the first floor. We have a second floor that leads back to our tutoring center. And then we have about 56,000 physical volumes, a small DVD collection and a lot of space for our students to gather and study individually or together. So where are we? Our main campus is in Aptos, which is sort of in the center of Santa Cruz County. And we have another center in Watsonville. It's not a full campus. It's a cluster of buildings right in downtown Watsonville in South County. Around 15,000 students enroll annually from across the area. And we're a single college district. There are no sister campuses, just Cabrillo. We have that dedicated space in Aptos and we share a very small cramped space about half the size of this auditorium for the library and tutoring services and a small computer lab in Watsonville. And like most of you, the demand for and offering of our online services had to expand dramatically during the pandemic in 2020. I wasn't there yet. I was involved with doing the same darn thing in Carson at Cal State Dominguez Hills. And like they and us had a problem where most of our course reserves, those textbooks and other instructional materials were pretty much only available physically. And we could not check them out during our pandemic closure. We were not allowed to be on campus and our students just overnight lost access to the textbooks and other materials like maps and globes that were very important to them. So a little bit more about our students in 2020, calendar year 2020, 47% of our students received some level of financial aid, 47%. In our 2018 real college survey, the real college movement is really awesome. You should look into it if you don't know anything about it. They did a survey for us about our students' situations. 40% said that they had food insecurity in the prior 30 days, 61% said that they had insecure housing in the previous year, and 22% said that they had been homeless in the previous year. Now this is prior to the CZU fire. The CZU fire changed the landscape dramatically for our students who come from mountain communities in the Pajaro Valley. So these numbers have only gone up since that time. And then we additionally had a focus group report from CCEAL where in particular our Latinx students expressed challenges of not being able to afford the required textbooks for class and described it as stressful, therefore causing students to feel unprepared with thoughts of withdrawing from the course. So Cabrillo College is a Hispanic serving institution, meaning that we enroll at a minimum, it's a federal designation at a minimum 20% of our student body is Latinx. Our current number is somewhere around 40% of our student body. So this is a real issue. This is an equity issue. This is an access issue. If students can't get the book, they're not going to take the class. If students are finding that they are spending money on a textbook instead of food, instead of gas, instead of medication, instead of housing. So sometimes I choose to buy course materials over buying food. This should say a lot about the cost of education. It is very frustrating to me that a book I will only use for three months costs me to paychecks. The population least able to afford anything is forced to pay inflated prices for the tools required for a chance to succeed. This is from an affordability survey that my colleague Aloha Sergeant conducted in 2019. Real quotes from real Cabrillo students. So our problem again, coming going back to a problem statement, we shut down because of COVID for 17 months. No textbook access for all of these different materials, blown boxes, globes, all the things that you need to do your work. And then the library licensing problem. I'm sure you're all very familiar with this. There are some titles that you just cannot get in electronic format for love or money, or for a lot more money than what you have available to spend, right? So many of the traditional textbooks, especially, we started to see those prices double, triple overnight. I went to buy a book at my old institution where it had been, I think, $120 for a three-year license, and all of a sudden it was $1,200. Forget it. Forget it. I had to call the faculty member and say, this is what it is, and they didn't believe me. I sent them a screenshot, and they said, okay, can't use that book anymore. So these resources, personnel time and budget for materials are very tight. And then we were really working on establishing equity for our students. So I'm not sure how much you heard about the zero textbook cost and low textbook cost priorities that the California Community Colleges have been tasked to engender. But this is a really big project. In the last budget cycle, the governor allocated $115 million to the community college system to set up ZTC zero textbook cost pathways, at least one degree program. Right now we're in that planning phase. At least one pathway through, general education, major courses, that a student could take that degree path and graduate with an AA. Either an associate degree for transfer or a straight up associates. So each college is working on something right now that in three to four years time there should be at least one pathway through to an associate's degree or to a certificate that has zero cost. They may have to take very specific course sections, but that's something that we're aiming to do. Cabrillo's very close on several, we're mapping right now. And for those of you who are working with people to try to help them register for classes, this little logo down here, that dollar sign with the slash through it, that indicates in a course schedule a zero cost class. So that's something you can use right now to help people identify those kinds of courses. This chart, you may have seen versions of this somewhere else, but this is from the Bureau of Labor Statistics put together by a group that I'm less happy about. But it's a great example, college tuition, see hospital services, then college tuition and fees, and then college textbooks. Look at that inflation line. Because of the pressures of open educational resources and libraries saying enough, enough, we can't do this, and college students saying enough, that has sort of hovered, the price hasn't really grown in three, four years. But it may just do so again. We've got to keep the pressure on to keep textbooks affordable. So one solution that we came to the conclusion that we had to find a solution beyond just buying physical materials, telling people that they were out of luck if we couldn't get the licensing, and that's through control digital lending. So how many of you have heard of control digital lending before? Only a few of you. Okay, so there are three basic principles to how control digital lending works. First, the library must own a legal copy of the physical book, either by purchase or by gift. So I have to have a physical copy of the textbook for Biology One on my shelf in order to loan it out digitally. And I have to maintain a strict owned to loaned ratio at lending no more physical copies than what we legally own. So let's say I have three copies of that biology textbook. I can only have three simultaneous users of the digital file. No more than that. And then I have to use technical measures to ensure that that file cannot be copied or redistributed. So I have to make sure that it can't be downloaded, it can't be printed, and that it stays in its kind of lock box. I can't stop somebody taking a picture on their telephone, but I can keep it from being pulled down in its digital file format as a whole. So think of it like some of the more locked up digital things that you have. We do that with these books. So the way that we did this is that we licensed a software add-on for our integrated library system. The community colleges and actually all of the UCs and Cal States use a program called ALMA, and we bought the digital asset management system called ALMA Digital. It was originally developed to share out digitized archival material, so images and photographs of sculptures and things like that. But like Content DM, for those of you who might be familiar with that. And the settings allow us to keep that strict owned to loan ratio to make sure that people are authenticated, they have to have a Cabrera College card that has access to online materials in order to sign in and access these books. We also built a collaboration with campus partners. So my colleague Aloha, who I mentioned earlier, wrote a faculty and staff grant to secure additional money for the seed of our collection. She received $9,800 from our college foundation. And then in her presentation about what this money would do at a foundation meeting, a benefactor stepped forward and provided another $25,000. That money's almost gone. What we spent buying books. Around 200 titles, many more copies than that. We tried to buy used as much as possible to make it stretch, but it's almost gone. And we've barely, I feel like we've barely made a dent, but I know we've made much more than a dent for our students. So that grant and donation support really helped. The collaboration with campus partners, back to that, we worked with our Accessibility Support Center to borrow their lovely, quick as lightning overhead scanner. After a while, they needed to use it too for their students to support their students. So we then augmented our workforce through grant dollars again, from the COVID education support grants and assigned some student and temporary workers to do a lot of the scanning and remediate those PDF files as much as possible. You can spend days remediating a PDF, particularly one that has a lot of diagrams, mathematical equations, things like that. After a certain point, we end up referring folks back to the Accessibility Support Center to get the deeper support if we can't bring that file all the way up to stuff. There's just not enough time. So things that made this very successful for us, having really committed personnel. The emergency solution that we had come up with at the start of the pandemic was not working. It was not sustainable. It was really time consuming. And we needed to figure out what was going to happen after the emergency situation, the immediate, oh my gosh, all of our classes are online. We can't help people in person. We had to figure out what came after that. There's also a realignment of our institutional priorities. Equity perhaps was not as strong of a focus for our administration prior to COVID. I hate to say it that way, but it was a very different environment. And the faculty as well did not necessarily understand how much their books cost when they were assigning them to their students. They were thinking, this is the pedagogically correct thing. This is what I need. This is what we're going to use. I'm comfortable with this text. It has some great add-on things. Sure, let's have them buy the thing with the Access Code. Well, when the students are coming to them and saying, I can't check this book out from the library anymore, I have to drop your class. And they ask why. And they say, because your textbook is $250, it wakes them up. And it helps them to see the inequity in what they're doing. And we actually have a mandate, legislative mandate, to find the lowest cost materials possible within our academic freedom to assign the items that are pedagogically appropriate for our students. Also, last year, we reopened in the fall of 2021 to reduced hours and many fewer students in person. We still had a majority of our courses online in fall 2021. Yes. I know, time is a weird circle, right? And we did not have nearly as much traffic in the building as we did pre-COVID. So we had a little bit of latency on top of being able to hire for more hours. We didn't need as many people on the desk or in the building being active and out there and making sure people were wearing their masks and all of that stuff. There just weren't as many folks around. We also spent some serious time doing some training and had support for finding the right tools. So we purchased some additional lightweight overhead scanners, just really little book scan cameras. And Aloha spent a lot of time digging deep into the materials and making YouTube videos that were really helpful that walked through from soup to nuts, how to make, how to scan a book, make the PDF accessible, get it to the right resolution for our Alma Digital installation, and make it go. It was really great. Also delegating. Once the workflow was pretty much figured out, we distributed it as quickly as possible so that we could scan as much material as we could and more people knew how to make the system work. So we didn't have a single point of failure or one poor person who was doing all of the things. We couldn't rely on just one human being who had already been pretty close to burnout by this point with all of the demands that were on them through the pandemic. We also have a robust community of practice. While Cabrillo might be the first to go live with control digital lending, we are not the only community college that is working on this. There are several colleges here in the Bay Area that are also beginning to offer online textbooks in this way. And finally data. We're able to get a lot of information about how many students are accessing these items and we're reporting that out. We're reporting that as checkouts to the annual library data survey, which is the analog of your public library survey, to our chancellor's office. We're reporting it to the Association of College and Research Libraries, ECRL, as checkouts, book checkouts, and to our benefactors. Like having some hard data early really helped us with getting that grant donation and that additional benefactor support. So what we would change is probably our timeline. We ramped it up super, super fast. We knew that we did not want to keep doing what we'd been doing for access any longer than the spring 2022 semester. So we moved quickly to get the subscription to Alma Digital up and running and then to get scanning going. And it was a very tiring end of the fall semester over the break into January for our folks. We were putting up books all the way through the spring semester and then summer as well. We had a deadline. We had to spend our grant money on personnel by early May and then we didn't have all of the fall books in time so we had to get other people involved pretty quickly. It was really fast. I'm also concerned about our long-term funding and sustainability since we're almost out of the funds that we secured to start up the program and we have a small budget supplied by our student senate to support textbook purchases more broadly. So now we have not just two locations but three. We have control digital lending. We have our face-to-face services and Aptos and then also our courses to support in Watsonville about 12 miles away. I'd also go back and distribute the labor out at an earlier point because it's still even though we did start to distribute and delegate it was still a lot of work over a very short period of time from one human being too much and I'd like to have spread that out. So that's something to keep in mind is that you do need a project team to get something like this up and running pretty early on. So next steps are setting up a sustainable workflow. Right now we really only have two or three people who are trying to do it. Our students have graduated and moved on and the library is a lot busier so they're on the desk and they're not available to scan and troubleshoot the way they were before. And again that regular source of funding, big issue for everybody for everything but the demand and the checkouts on this is just it's orders of magnitude greater than our physical collection. And then like I said earlier faculty really are wanting to go after zero and low cost resources now. They have really that the pandemic has brought home to them how much this costs. There's an entire department that is nearly finished completion of conversion to zero textbook cost our early childhood education department. Historically the most expensive textbooks or among the most expensive for the people who are earning the least in the end. So they see this as an issue of equity. We have a textbook affordability committee as well that has started up to work on this with folks and help them either find these resources or to find lower cost materials. Some disciplines will never be zero cost. That's okay as long as we can get lower cost we're doing really well. And also continuing to cultivate that relationship with our accessibility support center and making those connections with them and with other professionals across campus and across our community college system and within our community as well. The PDFs are what they are. They're not perfect but they do work for most people. We need to have the good relationships to refer people out who need more support than what we are able to provide. So I have a call to action for all of you. Even if you're not going to set up a control digital lending platform at your library or you don't see how it's really appropriate for your situation just support digital rights of ownership for libraries. We all license these things. Stop renting and start owning as much as you can. It is difficult but I think it's doable. Also learn about your US copyright law and fair use applications and educate your patrons and your boards. This education piece is what got us through to a yes. Talking about what it means to our students. Write letters, be supportive of the folks who are on the front lines and taking the fire for us and be loud on social media about what textbooks cost. You can look it up in the bookstore. There's a connection in most community college course catalogs as well so you can see how much that chemistry textbook I'm picking on the sciences but social sciences are not immune to this either. You can see how much these things cost and talk about textbook broke. Talk about eBook SOS. We need help. Discuss community impact. Who's harmed if we can't get these materials in digital and accessible formats? If you only have a phone and you're trying to look at something is it accessible? Is it visible? If you can't get to the library or you have really crummy wifi, what can you load? What can you get? Also, for those of you who are looking at things like contracts, read those licenses and push back. We have purchasing power, especially consortia that go in together on things. Look at those licenses. Make sure that they work for us and not for the vendor. Look at those terms of service and address poorly written contracts. You can get help with this as well. There are organizations out there that will help you look at contracts if you're looking at things on an individual library basis and you're really not quite sure what you're reading. It's okay, ask for help. Find your friends who are doing this work already. Hi, I'm here. I'm happy to talk about this. There's some questions I'm not gonna answer on camera but there are others that I'm happy to talk about on the phone or other ways because this is a really important topic and a really important issue. And if you can, if you are gonna set up a program, just make sure you check in with somebody. This says talk with counsel to set up your program. That's a recommendation from the folks at Library Futures who run the website controlled digital lending.org. They recommend talking with counsel just to make sure you understand all of the ramifications of what you're up to. I think that's a good idea. But find someone who understands intellectual property. And I would be remiss if I did not call out in specific the people who put this together. I'm the talky person. They're the ones who really did the lion's share of this work. Aloha Sargent researched and found this all-medical platform and brought it to me and to the community colleges. And we're at, I think somewhere around 30 or 40 of the 115, 116 community colleges who are implementing some level of CDL. Kelsey Shapiro and Rebecca Hine are intrepid public services, library technicians, have done so much work to Kelsey in coordinating and understanding what CDL is to explain to people and in coordinating the work of our student colleagues. And Rebecca has picked up most of the scanning now that we're much busier in our physical buildings. And then here are all of our student colleagues. Colleen, Omar, James, Itzel, Lexi, Sam, Jordan, Fiona and Wattee, they answer questions, they scanned, they promote the service. Several of them are on our student senate and are real cheerleaders for us. They're helping me get more money. They're really, our students are our partners in this. They're why we're doing this. We want to support them and we need their support in return. I've included some resources here. I'll make sure that these slides either go out in email or that they're uploaded to the PLP site. But control digital lending by libraries is the main source for a lot of this material. Library Futures puts on great programs and has some really great connections for CDL. I can't recommend Copyright First Responders enough. Kyle Courtney is one of the progenitors of the movement around control digital lending. And this project, Copyright First Responders, this is baby, has anybody heard of them? Yes, I am a Copyright First Responder. I took the training prior to the pandemic. It was one of my last pre-pandemic things. It was one of the best professional development opportunities I've ever had. There's also an implementers group, a lot of academic libraries in here for some really obvious reasons. You got the money, you got the time, generally. They have open forums and some practical support. And then Spark North America. They are one of the groups that might be able to help you with looking at your contracts and understanding what can and cannot happen. So I finished on a little bit on the early side. I don't think anyone will mind. This is my cat, one of them. Her name is Vantablack. She's not that small anymore, but what is a library presentation without a view of a cat? We have a great Instagram channel as well at Cabrillo College Library. You can see a lot of our students in action. And learn more about what we're up to on the other side of the hill. And I have cards too, but my email address is up there. It's missing one of the T's because they only use eight characters in our emails. But are there questions for me about CDL? And please don't be offended if I say, you know what, I'm not comfortable answering that because I am not a lawyer, but I'm happy to answer questions about our program and what you can do, maybe. Hey, thank you. This is kind of like a basic question. Curious if students who are accessing these textbooks, are they able to print certain pages out for like notations? No, they cannot print. And that's one of the pieces of this, right? That you can't duplicate it. You can't, I'm trying to go to, let's see if it will go for me. Cabrillo.edu, slash library. You also have to be, oops, of course, talking and typing, not one of my strong suits here. There we go, library. Yeah, you can't print, you can't download. And that's one of the things that folks have complained to us about, but we're like, but this is a copyright restriction. We're trying to really stay on the right side of the law as much as possible. So I'm gonna go here. So we have need a textbook, and we've set up two different search scopes, one that goes to online and one that goes to print. And we do have some traditionally licensed eBooks as well that are assigned. I'm trying to demo it, is it going? Here we go. So we have it set up by subject area, because that's how students are used to looking for things. So these are all of the different collections. And let's go look at an econ textbook. So intro to macroeconomics. And then here are two different books. And once I click on it, here's what that ends up looking like. We have two physical copies in the back. We literally have like five shelf ranges full of books that are dedicated to control digital lending. If we find that we need to flip one because a student really wants the physical book, and our physical copy that we circulate is checked out, we'll turn off one of these licenses and check out the physical book to the patron so that they're not denied use of that item. But if I sign in here, let's see what this looks like. No, you don't get to keep that. So here you see it's pretty, it's just turned the PDF chapters into a bright line. And then here's the reader itself. So I'm signed in and I can look at the chapters we have scanned. I can close the side mirror, but it's right here. And on a phone, it turns out really well. It scales properly for mobile, it's responsive. And you can return it early. They check out for two hours at a time just to talk about the mechanics behind it. So if I weren't to hit the return early button, it would just run out my time and then check it in for me. So that's what it looks like on the front and the back end has a lot of bells and whistles. So, yeah. So, what can public libraries do to support access better? Oh boy, that's a really huge question. A lot of this is possible because we had the infrastructure and the personnel available for the scanning. And it was really a confluence of great things. I think one of the things you can think about is like those books you can't get anymore on Libby or Overdrive or where they expire after 26 checkouts. That's all very familiar to me unfortunately as well. It doesn't make any sense for that to be what happens. I think looking at some of those titles that you can't get licensed and thinking about what would it look like for us to set up something, some digital asset management system and scan those items and make them available on a checkout basis for people who have cards in my system. It's a lot harder because we have outsourced a lot of that infrastructure honestly. It's way, way harder. If Alma Digital did not exist, we'd be having a really different conversation about what to do. This was available. We pay an additional subscription fee for this software as a service. We have a limit on how many files we can have in there. And I know that in the long term, what I'm hoping this is, is a step toward using more open resources, right? Using more open educational resources, helping faculty, it's supporting faculty in finding things that our students can't afford if they have to buy a textbook in the future. So I think what public libraries can do is support the community colleges and the Cal States and the UCs. Cal States really wanted to do this even pre-pandemic, but were shut down by internal counsel. I said that on tape, great. But it was shut down internally. I'm hoping that they're able to explore more now that more of the community colleges are involved and talking with your patrons about how much these cost, how much these books cost to license, how much more we're paying and what state attorneys general around the country are doing in suing publishers who, you know, I would love to see them as our partners more than they are. I really, really would. And I would hope that they would too, but that's not quite the relationship that we have right now. So advocating for better access, for lower prices, for owning rather than licensing, owning rather than renting. Just really quickly, what, thank you as well. Just really quickly, what overhead scanner did you use? We had one of those little bitty book scan overhead scanners and it's really a very manual process. The other one that we had, we actually, for books where we could, we sliced off the spine and fed it through. And if it was something that was a loose leaf, we just used our copier, honestly, to make the scans and then did a lot of, did some remediation on the back end. Just a chapter at a time, because more than that, and then the files get too large and unwielding and they don't load very well, especially on those mobile devices. Many of our students don't have a laptop or access to decent Wi-Fi, especially in the mountains. So they're dealing with their phone and dealing with campus Wi-Fi, and it's a lot easier if they're smaller. Yeah, so something that can make nice, small file sizes is very helpful. Joanna. Yes. Thank you so much for this. This has been so interesting and pretty radical. I was wondering if you could talk to us briefly just about the statistics, the use, and if you think that those might change as things open back up. Our statistics, I shared a spreadsheet in a MOBAC meeting back in the summer. Our statistics have been through the roof. We're getting checkouts upwards of 10 or 20,000 a week on these textbooks, maybe more. I haven't been following along quite as closely as I should have before coming today, but we have definitely in the first six weeks or the first four weeks of the semester, we exceeded all of our checkouts from spring semester total. Students are finding these, faculty are finding these, and putting the links in their Canvas shells, the learning management system that community colleges use, and they're hitting them, and whether they're in-person or online or a hybrid course, we have seen a real re-engagement with learning materials as a result of having them available online, and we own the book, we still own the book. So if everything goes haywire with this, whatever happens with the decision, which could be a year or more away, we still have the physical books no matter what else happens until someone changes what's assigned, but we do have those materials available for our students, and we do have physical books available for a lot of these courses that students come in and check out, and those have a two-day checkout period, we've lengthened it, and more students are using it. We also dropped all of our fines and fees, so the students are not afraid to come in and check out what they need, and worried that they might get dinged or billed if they keep something a little bit too long. So yeah, it's really staggering how much use we've had. A colleague at a different community college, still here in the Bay Area, said that one book of his had 30,000 checkouts just in the first eight weeks of the semester. Yeah, we're in week eight now, we started back at the end of August. It's been a really popular program, and so very successful, and our students are so, so excited to be able to use their textbooks, because if they couldn't buy it, they just weren't bothering, and were doing the best they could. I'm hoping that we can somehow tie things to student success, and see if there's a better GPA, a better completion, higher grades for the courses that have CDL textbooks available, or open educational resources, as opposed to the more traditional courses where students are buying expensive textbooks and access codes. But that's long-term. Yeah, okay. No, no, okay, go ahead. No, no, yes, I'll ask you off the tube. Okay. Oh. Okay, I wish, I was just gonna ask, have you heard any grumblings or communications from the publishers? Not yet. This is the first time I have spoken publicly about it. Then why do you think that is, oh. Well, partially because this is the first time I've spoken about it, but also because we have it so tightly locked down, and there are, and our vendor, this is, the vendor for our ILS is Ex Libris, and Ex Libris is part of the Clarivate suite of companies, which includes ProQuest. And the Ex Libris is marketing Alma Digital as a control digital lending solution. They see this as a market win for them to be able to do this, even though they have like big publishing on their broader portfolio, excuse me. So there's, they see the use case, they follow the law, and they see where this really is a game changer and a way for them to continue to have some sort of market capture, market share. So I think that both of these things can exist together. And what I'm hoping is that it makes some downward pressure on the licensing so that we can get these books without paying so much money that we just don't have any room to do anything else. My budget would be wiped if I had to buy all these books. Yeah. So I just wanted more clarification so that students get two hours with the textbook. And then it, I'm sure sometimes I could be frustrating for them. Right, right, it's two hours. And then if no one is waiting in line for it, so there's a holds list, so to speak, it's really more of a waiting list than a holds list. So if there's a wait on the item, then their session will expire and they're given warning that that's gonna happen. And if no one's waiting, they can renew it as many times as they like. But we started with four hours and that was too much. We were getting lots of turnaways. And really only two hours is fine for most people because by that point, they don't wanna look at a screen anymore. And if someone really starts to complain, we'll look at an alternate solution or refer them to the Accessibility Support Center because maybe they need more time with it for reasons that they don't wanna disclose to us and that it's not any of our business to know. Okay, thank you. Any other questions? Well, thank you all so much. It was my pleasure to talk about this. Thank you so much, Joanne, I learned a lot. That concludes today's conference. We do kindly ask that you return the plastic sleeves with your name badge just to the box that's located in the back, as well as return any paper surveys that you may have been holding onto that you picked up at the registration desk. The survey is also available as a QR code. And so we do ask, please do fill it out. We really value your feedback and it really helps us with planning for the coming year. As a final note, I would like to thank the committee or the committee would like to thank and acknowledge the Pacific Library Partnership staff and the staff from the San Francisco Public Library for support of this event. That includes the wonderful crew over there who handled our sound and recording. Because of their hard work, the recordings for this conference will be uploaded and available soon. So thank you all so much for attending and spending time with us today. And we hope to see you next year at Future of Libraries 2023.


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Okay, so first I'd like to thank the organizers for putting this meeting together and for inviting me And so today's talk is going to be some sort of a follow-up to Alexandra's talk yesterday And I will exclusively be talk about analysis of data that was collected by the group in Rome That and the data that Stefania explained how to obtain beautifully in the in the previous talk and This was what I'm going to talk about was also of course collaboration with Alexander Valchak And also with Francesco Ginelli at Abadian University So but first before going into Into my talk, I just wanted to to give a first slide about Maybe emphasizing the degenerality of collective behavior and especially of emergent collective behavior Not just in animal groups, but at any scale in biology. I think that's a useful thing to remember So there's you know, there's collective behavior even at the molecular scale if you think of allosteri for instance Corporating banning and then you know at the cellular scale like a neuroscience is an example of collective behavior of many cells together Or multi-cellularity problem and of course animal groups, which is what we most of us are talking about during this meeting So the the system again to talk about is a flock of stalling So this is the movie you already saw yesterday So maybe you'll have to stare at it so so much and this is the same slide you saw yesterday So this is the data that was collected by in a group of Irani Jardini and Andrea Cavagna in the past few years and They managed as you saw in the Stefania's talk to reconstruct the 3d position and velocities of up to you know thousands of birds in the same flock and And the amazing thing is the amount of coordination, but not just the amount of coordination, but also the wide length scales over which individuals are correlated with each other and When you see this as a physicist your first reaction is wow, you know this this reminds me of something and it reminds me of interacting models in in statistical mechanics the prime example of which is The ising model so you know it's this is a very old idea is the idea that you have spins that want to point in the same direction and at equilibrium Even if you're you have just have local interactions with the nearest neighbors You still get spontaneous mechanization of the entire system So you get a breaking of the symmetry and so the you know The idea that physicists have when applying this to biological systems, and I want to emphasize again that Physicists have applied this idea to many of the systems than flocking and and the collective behavior Is that maybe you can think of this as a paradigm for thinking about many interacting agents of any sort Put them on the network of interactions and maybe you'll get collective behavior in the same way you get spontaneous Mechanization so you can put for instance flocks of starlings on this and you know this idea sounds a bit maybe a naive You know say okay. Yeah, we're physicists. We know better than everybody else. So we just apply our tools But in fact, you know, you can do this construction explicitly and this is what this is just a summary of x and y stocks yesterday By using the principle of maximum entropy where you just try to have a probability distribution over the orientations of velocity of many birds in the flock and All you do is constrain the correlation functions between pairs of birds and what you end up with is precisely this kind of models of interacting spins that we familiar with in physics in this case is called the Heisenberg model and With this kind of thing you can actually produce the long range correlate the long range of correlations Simply from a from a short range of interactions So we're producing this idea from the Ising model that you get the the spontaneous order at the large scale from just the small scale and So so now what I'm gonna do is I'm going to try and first this construct this idea and and maybe explain to you why you know, maybe The doubt that fair criticism against this kind of idea and then you know, otherwise I would be I wouldn't be talking about it this way I will rehabilitate the idea at the end So what's what's the main caveat with this kind of approach is that it's purely phenomenological It's based on probability theory and maximum entropy, but then we give this interpretation in terms of physics of having a Hamiltonian But you know like a physicist have studied talking before you know independently of the Heisenberg model and They they had a very big different picture in mind. So let me explain this to you So so far, you know when I was just interested as an introduction. We implicitly assume a equilibrium, right? but there's a big difference between birds and and spins and this was realized of course, you know in the 90s as you will see is that birds They actually exchange neighbors the network is not fixed and this is very important for two reasons I mean first of all is that because it from the physics point of view with it brings it takes the system out of equilibrium So maybe this should question the approach of trying to have an equilibrium like inference procedure But even from the from the biological point of view like so, you know the exchange neighbors What is within this also entails is that maybe you know the the the effective number of interaction partners that each bird has is not the one That we we get from Instantly so let me explain this like if your bird basically as you you know, if you integrate information from your neighbors But you know if you if you integrate over some some timescale. So remember, you know what you learn from your neighbors before Then if you change neighbors over time Then you accumulate some information from from neighbors over a long time and therefore Over many more neighbors than you integrate at any given time, right? So it's basically a combination of evidence. You have a larger effective number of neighbors and from even from a physics point of view is very important because this means that you can actually Carry information physically So if you think about the alignment of spins for instance, basically the alignment is just done locally from neighbor to neighbor But all the spins are not you know, none of them are moving But here what happens is that not only you can transmit information by communication to the next individual But you also physically move around the network and so you can also Propagate that information physically and this from you know, in fact, this completely changes the phenomenology I mean the the behavior of this kind of system So this was realized in the 90s, especially by two and Turner in 95 and What they showed is for instance if you look at continuous spins in two dimensions, which is The sort of model one has in mind a continuous spin is just a continuous direction of motion But if you're in two-dimension There's a theorem that tells you that you cannot get all the in two dimensions You cannot get a spontaneous order of the kind I was showing for the for the ising model But if you include this this active Element the fact that the neighbors change then you you you know You basically rescue the order and you can actually get it into them and also changes the critical response and everything and you know these studies were basically Based on the study of the of the Vechek model Which is this one where basically each bird as a function of time is taking some sort of a special average of its neighbors To determine its next direction of motion So you see it's quite different model than the Heisenberg model so We thought about this and you know you see that here We we have what looks like two contradictory descriptions once one is an equilibrium description From which you can actually learn useful biology and phenomenology, but then you have this dynamical Picture which seems to predict different things even on the on the theoretical level So to to address this question. We decided to to go back to similar data and actually quite different data but Where now we don't just focus on the on the equilibrium properties which you may also view as static properties It's just single snapshots of the velocities of the bird and now examine the dynamics and try to learn the dynamics, right? So essentially and try can we learn something like the equations of motion of The flock or something of the sort as the Vechek model So of course to do this the first step is to actually record the dynamics and so this is what Defining I talked about So this is we analyzed You know the the flocks that she she or she and others are recorded So I'm not going to go too much into details there. This is this was already covered. So They managed to to get the identity in In positions or in three dimensions of all these flocks or all these birds in the flock and that way can reconstruct the collective trajectory of Foldables So this is a starting point. We we take these traces and try to analyze them to learn what are the equations of motion from the traces and So in doing this we we want to to stay a bit agnostic and follow the same kind of philosophy that we did for just looking at single snapshots and by this I mean that we We don't want to maybe assume the dynamics from the beginning But we want to learn it from the data from from first principles and And and to this we you know, we basically generalize the the idea that we had before But now instead of thinking of probability distribution over all the velocities of individuals in the flock we think of The statistics of all possible trajectories. So the collective trajectories of all the birds in the flock at all times It can you can do it this way. It's like it's like a network of interacting Individuals, but they also interact with themselves at different time slices, right? and So we describe, you know by probability distribution over the states of the velocity of the orientations at all times and In physics we call this in actions is where I'm writing this way It's just a fancy word for the logarithm essentially of of this probability distribution So we'd like to learn basically what this action is from the data, right? So again, you know, how do we do this? We need to make some assumptions and what we will use the same exact same trick as before the trick of maximum entropy so but now So we want to maximize the entropy of the distribution over trajectories But now we want to put constraints Not just on the correlation functions of pairs of individuals at the same time But also we'll go cross correlations. So the correlation function of one individual at empty with another individual at empty plus one and if we do this the the kind of Action that we get looks like this. It's just using the same trick of maximum entropy So you get an exponential form and here you get these Lagrange multipliers. They essentially enforce this constraint, right? So called J1 and J2. It looks like a complicated Formula, but it's essentially the same thing as before except that we added this link this links between neighbors across two different time points, right? Can view it as a we unfold the network in the time direction and By the way, this is also called maximum caliber when applied to this time direction. So Now we that we've done this Okay, so here I have the convention of TT plus one and then I'll move to you know T plus delta T, but you can get it's the same idea so we have this maximum entropy principle with the constraints on these on these two kinds of observables and The first thing is that one can show In a spin spin web approximation So the spin web approximation was already explained by Sandra yesterday But let me remind you what this means. It just means that the the the direction of flights the SI which are normalized vectors Are all very close to the common direction of flights of the entire flock. So we can basically You know summarize There's viable by how much they differ they deviate from from this main direction. It is this and this new Variable which is equivalent to s would just be called pi. Okay. It's just a deviation from the main direction and So the spin web approximation just means that these Fluctuations are small which is equivalent to saying that the flock is very polarized Which is indeed the case in the data that we've been analyzing So in this approximation basically and this is an approximate equation You can show that the maximum entropy distribution. I was showing before is equivalent to Stochastic differential equation or stochastic Recursion equation where each bird is basically taking some sort of weighted average over You know all the other birds with some weights mij given by this matrix plus some noise and where the noise can be is delta correlated in time, but can have some correlation structure and both m and C I just transformations of these two Matrices J1 and J2 which were the lack of multipliers Enforcing the constraints Okay, so here already you can see that this looks very much like a social force model I will try to each bird is trying to make some sort of an average of its neighbors So on the technical side, I mean the way we show this is because you know the whole process is a mark of chain and In the spinner approximation everything can be considered Gaussian because we just expand to second order And so it's just a mark of God, you know, it's called Gaussian process in some cases with collective Gaussian process. So we can just write explicitly the the form of the conditional Probability of going from one state to the next and this is what gives us this equation It's okay, so so we we've already shown and this would be turned out to be useful to have this kind of formula for inferring the dynamics explicitly But before we do that, we you know here we have a delta T which is somewhat arbitrary Parameter and you know, we will only know what to do with it So what we do with it is that we just send it to zero just take the continuous limit and And it kind of you know, it's a limit that sort of makes sense It's also it means that on top of the constraint on the same time coefficient function Now we replace this cross-collection function by the correlation function between The direction of light and how it changes in time It's a correlation between these two things and this will be our new constraints and the continuous limit And if you do this then the social force model I just showed Now actually looks like a stochastic differential equation Which has the same interpretation as before Where each bird is trying to adjust its its direction of flights according as a weighted average of its neighbors And if you look at this and you start it you realize it's exactly the same thing as the Vichyck model Only you can have arbitrary weights you can have arbitrary Correlated noise, but it's the same kind of structure so Okay, once we have this we still have a many things to parametrize in principle So we have this for instance the correlation of the noise Well, you know to simplify we'll assume that the noise is actually not correlated between different birds, right? That's a simplification This allows us to so we just say has some some delta. I forgot delta ij So it's basically determined entirely by this parameter t d here's just a dimension of the problem So you can forget about it and t is can be literally Interpreted as a temperature gives you the amount of jitter that there is when each bird is making this its decision another nice thing about this dynamics is that if you assume that the That the network of neighbors is constant and also later has its symmetric Then you can actually show that this equation has a steady state and It's in fact an equilibrium steady states, you know technically from the physics point of view and it's given by exactly this Which is exactly that has a model I was I was presenting when As a consequence of the maximum entropy principle on single snapshots, right? But here you see here. There's a big this is there's a somewhat important difference Which is that now we have explicitly this temperature here, right? So when we're doing the static in France or the equilibrium in France, we did not see this t because it was basically Folded into the J matrix was here in principle from from this description. You can distinguish the two things We'll see that we can actually do this we can actually do this and for this this thing Okay, so I already said how to parameterize the noise now We're also going to make an assumption about the nature of the interaction of the interaction matrix so this interaction matrix Jij and To do this we will make an assumption that's that's been somewhat That's been motivated by by previous work We'll assume that the interaction matrix is such as a decaying function of the order of the neighbors that you're interacting with So you interact with your first neighbor with the strength you interact with the second neighbor with this You know a bit a bit less with your third neighbor a bit less So you number your order your rank order your neighbors like this and then you you determine The strength as a function just of that rank and not of the distance or anything else just a rank Right and was shown in the context of static or equilibrium in France That's this is actually what you you know you get an actual exponential decay. You can see it here on the log scale Very nicely. So that's what we'll assume here We assume this form but of course once we have this we We also know we left with two parameters with J So J can be interpreted as the interaction strength and NC Would be interpreted as the interaction range. So it tells you To to what you know up to what neighbor you really effectively interact So that's it. I mean that the model is not parametrized So we just have three parameters the interaction range interaction strength and the temperature that was considering the noise that I was talking about before and Now that we have that we we just use maximum likelihood fit which can be shown to be equivalent to solving the maximum entropy model you know using some Some integration methods that I will just briefly go over now. So Let me explain why we need this method in the first place So if you look at trajectories of this of these birds in the flocks You notice that they often have this kind of oscillations, right? And that's because you look at the center of mass or the barycenter as I was saying and If you if you do this because the the birds flap the barycenter goes up and down, right? So you get this oscillation and and because of that It's somewhat ultimately limits the effective sampling rate with which you're taking different snapshots and limits precisely to about Sorry, it's ten hertz. It's point one seconds. Okay, there's a mistake here so the problem is that With such a long time the the usual integration methods that we use Which is all those methods is is likely to be in precise. So in instead what we do is that we integrate We linearize the equation And we integrate it explicitly as a function of time between t and t plus delta t Okay, so this is done here and this is only valid if you have a fixed network But it's it's it's exact if you assume a fixed network and you if you're in the spin web approximation So just more technical details when once you have that you have an explicit expression of the likelihood and Then this is exactly this is this thing that we maximize with respect to our three parameters and see giant, right? which are all hidden here in these in these formulas t is here j is here and C is here So we do this maximization and we get an answer so but first before Actually talking about the application of this to the data Well, we first wanted to test it on synthetic data to make sure that the method actually works so You know, we just simulated The process we want to infer right and then we try to infer back So here we put the birds in the in the box to to avoid any any problems with the periodic boundary conditions And then we we take the data as if it were Experimental data and we try to infer back the parameters of the model And so, you know, this this is supposed to show you that it works very well but also it's it's it's the important point here is that You know, we do with different value of the true interaction range and see where we get back So it works well and we do it here for two different sampling rates So delta t here is the sampling rates with which we actually know It's not the rate with which we we do the simulation, but the simulation is done in continuous time But then when we do the inference we only allow ourselves To have one snapshot every second here Right So if we use Euler's methods or his method is just integration, you know, simple integration rule You can see that when this delta t the some the sampling time is large You you're gonna get you're gonna make a big error on the inferred On the inferred range, but if you use this exact integration method I was just telling you about then that case you get the right answer or most no matter what delta t is Okay, so this is to show that you know, it's not not it works and it's a useful step to go beyond Euler's approximation then Still on synthetic data we can ask Okay, so we're gonna get an answer for NC for J and for T and Can we make a comparison with what we would get from just so this inference here was done on the as I said on the On the dynamics so trying to learn directly the equations of motion but can we compare to what we would get if we did the so-called static inference or the equilibrium inference and this is what this gives and You can see that the the answer is actually depends on on the parameters of model so When the interaction strength is fairly large You see that the static and equilibrium inference give pretty much the same answer So equilibrium here is it's just doing inference on on the single snapshots Whereas the exact inferences is actually doing it on successive snapshots So in that case you get The right answer, but now imagine that the interaction Strengths is a bit lower in that case You can see that when you take the equilibrium inference you completely overestimate the interaction range And this is exactly what I was telling you about before which is that when you do this equilibrium inference You know, it's actually what you capturing is the effective number of neighbors and Here the effective number of neighbors is actually much larger than the instantaneous one. It's one you get this discrepancy so Why do you get the right answer in one case and not in another case? I leave that to a further slide, but it's just something for you to to think about Now, you know the the real question for us is if we look at the data and what in which of these two situations are we and The answer is that we in this situation, which is the good one in which the two things agree so here this is application to the actual flux that was just showing before and What I want you to really You know, what I really want to stress is that the two answers here are obtained by completely different types of information This is just obtained by single snapshot. They're just looking at the state In the statistics of things you see in a single snapshot Where's here? This is obtained by learning what happens when you look at one snapshot and then the next and It's really a non-trivial Prediction that the you know the two things should agree because it really means that a steady-state distribution here Can be can be predicted as a consequence of the equations of motion and again, you know here you know Here we I'm showing just interaction range the fact that we get it right So these are 14 flocking events and each of them has a different interaction range And there's something else that we can infer which is the interaction strength and temperature and that case where we need to compare Of course is j over t because I said it's folded into It's folded into the the j in the in the equilibrium inference and For that also we get a fairly good women's So why is it that after everything I told you that? The other equilibrium aspect the fact that the neighbors change that the effective number of neighbors should be higher How come that this actually still works on the actual data that the fact that this equilibrium inference gives the right answer so to speak Well to understand this I need to maybe introduce the time scales that are in the problem So you you you can think of I think that two main time scales One of them is how do birds? How fast do birds align with the neighbors? So imagine you have a bird here, which is misaligned with all its neighbors and Because it tries to it's it's it's driven by this social force. They would try to realign with the neighbors and Like this and it takes some time and that's what we call towel relax. It's a relaxation time of the aligners So that's one time scale and then there's a second time scale, which is How fast it takes for a bird to change its neighbors because it's Yeah, sorry the first one this recession time time scale as I argue in the next slide and a couple of sites It's essentially given by by J times NC. You can see it scales like one of the time So tar relax is given by the inverse of this But so the second one is how fast each bird Renews its neighborhoods So how long it takes to completely to have a complete turnover in the set of neighbors, right? and that's what we call town network and That we can directly read off from the data I'm not going to show how but just looking at the auto correlation function of the of the net of the network neighborhoods so What happens in this system in the actual data is that if we recall these two guys you see that the The timescale that governs the network rearrangements is much slower than the ones of relaxation So what this means that what I was saying about the birds keeping memory of the alignment and carrying it to the neighbors and everything That's not actually really true because they keep very little memory of Things over time. This is what this time relaxation timescale means. So it's but it's less than a second, right? So after, you know, less than a second they completely forgotten information from previous neighbors And since they changed neighbors of the timescale of 10 seconds by the time they've renewed the neighborhood the neighborhood They will have forgotten the information about the previous neighborhood So in other words, they always, you know, really aligned with the local neighbors that they have now and This is essentially this is really the the the fundamental reason why The the equilibrium inference works and now we can come back to this thing I already showed So this was the case where it didn't work and the reason why it didn't work is because in that case the tau relax So which is given by the inverse of this was of the same order of magnitude as the network relaxation The network rearrangements and timescale you can see the ratio of the two in this in this plot here was about a hundred Sorry in this plot was about a hundred to get a clear separation of timescales Why is in this case where you get the overestimation? It's when it was of the order of one Okay, so now you might might be worried that You know, does it mean that you know have to throw away all the nice theory of turner into that was introducing the talk with And answer answer, of course, is no we shouldn't do that Right and the reason is because you know the this relaxation timescale is not the only Timescale that that matters in fact to so to do this you you It's useful to to take the check like model and Put it on the square lattice, right? So forget about the name the neighbor exchanges because I already said that it's slow compared to the other timescales And let's assume that all our birds on the on the regular lattice in that case You can take some continuous limits in which this this pie, which is basically remember the fluctuation With respect to the main direction is is is driven by this equation and You know we can go in four-year space and write the so-called Green's function that describes fluctuations of this and from that you can actually write an equation for the relaxation autocorrelation function Which takes this form in the end right and so so forget about the details may be here But this tells you basically how much power there is in the fluctuations at each At each k where k basically gives you another man into the one of the distance, right? What they said when if you look at this equation You see that you have a one of a k squared and this thing actually diverges when k goes to zero So it means that you get so-called infinite power of fluctuations for very very long timescales right and When you when you end that situation Also, if you look at the relaxation when k goes to zero the relaxation here is infinitely slow so what happens in the you know in in a system like this is that Things the you know any perturbations will propagate to the entire flock, but it will take infinitely long to do so So if you think of this relaxation here the global relaxation time it would be given by the By the by the cutoff here in k, which is 1 over L And is given by this thing that diverges with the system size L is the system size in this case So the global relaxation timescale is extremely large if you have an infinite flock However, that's not what concerns us here because what we really care about, you know, I'm sorry Say it's is is really the relaxation timescale Locally right the relaxation timescale respect to just your neighbors and That's given by you know the same equation here But instead of putting cutoff at one of L just the size of the entire network It's given by one of RC where RC is the is the range in the interaction range expressed in Expected expressed in an actual length right in that case you get this star relax Which is pretty much what I was assuming before with this corrective factor, which is of order one What's really important here is that the relaxation timescale of the wish the inference is done, which is a local timescale Is fast enough right it doesn't mean that the scale of the entire system is fast and Okay, so So that's it. I mean we we you know at this point. We're fairly happy because we we've done a Dynamical inference we've done a static inference the two things agree. We understand why But there's a but there's kind of a problem Which is that we've been assuming some dynamics that's inconsistent with some other features of the data and let me just Tell you briefly before before wrapping up. Well, that's the problem So in the previous paper The wrong collaboration Showed that there was a ballistic transfer transport of information in the in the flock meaning so they saw that during turns Basically what this means is that when some bird is changing direction the way this information propagates Through the rest of the flock does it in the in a linear way in time like a wave, right? but if you think about the v-check model or the kind of model that we have this kind of model and you know the What this model would with instead predict is that when you have a turn the information Would basically decay as a function of distance and the reason for that is because if you take this equation and you Do the same trick of taking the continuous limit. I just explained before if you look at the structure of this equation It's essentially a diffusion equation. So the diffusion equation that you get you get a but you get a perturbation somewhere and then basically Diffuses very slowly like the square root of time and also decays So not exactly what we will expect from from from from these data And so to to rescue this you you need basically that's why we They showed in the first paper and then we we proposed a more detailed model in the second paper here is that you actually need to Go to a second-order dynamics and basically what so this is the equation But basically the basic idea is that it's like adding a mass or adding momentum to your system. So If you think of a of a of a dental see later We add this the second-order term which corresponds to this inertial term and that's what will allow the The you know to waste to propagate because if you linearize this equation the same way I did before then you get an equation of that form and So this is the damping as before but here now you see this looks exactly like a wave equation Right, so you get a second-order derivative in time and then it's known, you know from since the 18th century that this kind of equation can support wave solution and therefore Can explain why information propagates linearly and we know we showed this Explicitly by simulating this model and by showing that a turn can actually Propagate so that the entire flock can turn together instead of having just a few leaders and Do the turn and then the flock splitting So Okay, so says, you know that that's another piece of information for you and basically You know what we need to do at some point is is reconcile these two things. So these are my conclusions I mean the domain the main really message I want you to to remember is that you know in the real flux there's a separation of time scales between the the rearrangements of the neighbors and the relaxation timescale and this is why The this this equilibrium inference and dynamic inferences give the same answer and Then you know the caveat is that you know really to explain what happens in these flocks We would need a second order dynamics with this behavior of mass to explain inner propagation So what we need to do next is to do this kind of inference both in birds But also in swarms because as Andrea showed yesterday There's also evidence for this kind of second order dynamics in swarms and with that I thank you for your attention