 In another study, McKenzie, Gibson and Steven Stillman analyze the effects of a Tongan migration lottery program to New Zealand, finding a negative impact of emigration on the resources of remaining household members, as remittances don't fully offset the shortfall in labour earnings; more generally, this suggests that comparisons of migrant and non-migrant households are likely to be biased due to self-selection of both households and household members into migration.By contrast, when studying the impact of New Zealand's seasonal worker programme on households in Tonga and Vanuatu, McKenzie and Gibson observe it to strongly improve those households' income, consumption, savings and standard of living.Most recently, in research with Rapoport, Albert Bollard and Melanie Morten, McKenzie has challenged concerns that educated migrants remit less, finding instead that - while results differ across destinations - more educated migrants remit on average more, with the effect within that group being mainly attributable to the higher income itself rather than to background characteristics.