How flags work

A flag is several results from your analysis, joined with underscores inside epi{...}. Each scene's Flag table lists the parts in order, what each one is, and its format. For example, epi{OR_Q_W} might mean a pooled odds ratio, Cochran's Q, and the largest study weight.

Why several parts

One rounded number has only a few thousand plausible values; three independent results have billions. Nobody can guess a flag, and no single shortcut gives it away. Some parts are converted with the everyday arithmetic of epidemiology (an odds ratio to a risk ratio at a stated baseline risk, a risk difference to an NNT rounded up, an SE from a ratio confidence interval). Those conversions are where real analyses go wrong, so they are part of the exercise.

Formats

You may paste unrounded output: numbers are rounded to the declared places for you. Every scene is built so that each part sits well away from a rounding boundary under every defensible method, and that rounding early or late gives the same flag. The console shows will be checked as before you submit, so format slips never cost you.

What the checker tells you

Right or wrong for the whole flag, never which part. Telling you that two of four parts are right would let anyone solve them one at a time. You get ten submissions an hour per scene, one every ten seconds, and wrong flags cost nothing.

Marlow's notes

Each scene has one hint: a note Professor Marlow left in the margin of his case file. It is a famous line, or the title of a book, film, play, or painting, with its source. If you see the connection, it points you in the right direction; if not, you are no worse off. Notes are free. After a solve or a surrender, the solution explains what the note meant.

Solutions

Signed in analysts can open a scene's solution after closing it, or surrender it to read the solution now. A surrendered scene never earns points.