I’m Linch Zhang, an amateur COVID-19 forecaster and generalist EA. AMA

I am do­ing an Ask Me Any­thing. Work and other time con­straints per­mit­ting, I in­tend to start an­swer­ing ques­tions on Sun­day, 2020/​07/​05 12:01PM PDT.


I am Top 20 (cur­rently #11) out of 1000+ on covid-19 ques­tions on the am­a­teur fore­cast­ing web­site Me­tac­u­lus. I also do fairly well on other pre­dic­tion tour­na­ments, and my guess is that my thoughts have a fair amount of re­spect in the nascent am­a­teur fore­cast­ing space. Note that I am not a pro­fes­sional epi­demiol­o­gist and have very lit­tle train­ing in epi­demiol­ogy and ad­ja­cent fields, and there are bound to be con­sid­er­a­tions I will in­evitably miss as an am­a­teur fore­caster.

I also do fore­cast­ing semi-pro­fes­sion­ally, though I will not be an­swer­ing ques­tions re­lated to work. Other than fore­cast­ing, my past hob­bies and ex­pe­riences in­clude un­der­grad in eco­nomics and math­e­mat­ics, a data sci­ence in­tern­ship in the early days of Im­pos­si­ble Foods (a plant-based meats com­pany), soft­ware en­g­ineer­ing at Google, run­ning the largest util­i­tar­ian memes page on Face­book, var­i­ous EA mee­tups and out­reach pro­jects, long-form in­ter­views of EAs on Huffing­ton Post, lots of ran­dom thoughts on EA ques­tions, and at one point be­ing near the top of sev­eral ob­scure games.

For this AMA, I am most ex­cited about an­swer­ing high-level ques­tions/​re­flec­tions on fore­cast­ing (eg, what EAs get wrong about fore­cast­ing, my own past mis­takes, out­side views and/​or ex­pert defer­ence, limits of judg­men­tal fore­cast­ing, limits of ex­per­tise, why log-loss is not always the best met­ric, cal­ibra­tion, analo­gies be­tween hu­man fore­cast­ing and ML, why pure ac­cu­racy is over­rated, the fu­ture of fore­cast­ing...), rather than do­ing ob­ject-level fore­casts.

I am also ex­cited to talk about in­ter­ests un­re­lated to fore­cast­ing or covid-19. In gen­eral, you can ask me any­thing, though I might not be able to an­swer ev­ery­thing. All opinions are, of course, my own, and do not rep­re­sent those of past, cur­rent or fu­ture em­ploy­ers.