system
A chat on subreddit /r/wallstreetbets
human
3124 is the 13D MA. I hope you aren't doing your technicals using an ETF that's imperfectly tracking the actual underlying.

gpt
SPX but I'm using 13 day EMA actually. 
  
 As for using SPY vs SPX, SPY follows certain TA methods as well. I look at SPY, SPX and ES.