Hacker News new | ask | show | jobs
by lern_too_spel 2222 days ago
That was a shitty code review. Seeding issues like the ones cited don't affect the results of a Monte Carlo simulation, and there are tests in the repo, just not automated ones.

The section you quoted shows the reason for the review's sloppiness. The reviewer set out to find a way to justify their own beliefs instead of to actually read the code.

3 comments

> That was a shitty code review

Damn straight. The only sense in which it was not a shitty code review, is that it didn't actually review any code. Looking into the linked tickets is a time consuming faff, but people should actually do it before taking the blog post at face value.

I agree. Moreover, the cited bug ("predictions varied by around 80,000 deaths after 80 days") doesn't really seem to impact the over all policy implications: no lockdown means exceptional number (400 to 480k) of deaths.

Unless the entire simulation is bogus, it comes off as nitpicking.

Seriously?

Doing a Monte Carlo simulation means you adjust the seeds to get different runs. It doesn't mean your program can read uninitialised memory or reuse variables that weren't reset to zero and still be correct.

Where are people getting this idea that you can just average away the results of out-of-bounds reads and race conditions?

What does reading uninitialized memory or reusing variables that weren't set to zero have to do with seeding issues? Read my comment again and reply to its content instead of making up a comment that you would like to reply to.