This is a logical fallacy that is unfortunately rampant on here. It's an ad hominem - the source may be a bunch of shitty people, but if we're arguing that we shouldn't accept something, attack the actual content of the message.
It's generally quite easy to do so when the source of information is biased, so dismantle the message if you want to argue about how it's incorrect.
It looks like these numbers posted were very low effort and lacking any real context whatsoever, so it shouldn't be too hard to rebut them.
It's not entirely an ad hominem. The original claim contains an implicit appeal to authority in citing the link to the blog. Saying that the authority cited is not actually a valid authority (due to a known bias) is not quite the same as ad hominem.
We resort to reputation to calibrate the burden of proof. If the source cited is not a valid authority, that doesn't make them wrong, but it does make it harder for them to establish a claim that merits rebuttal.
But the multiplication does not support the assertion. I am sure that many people biased by skin color can perform multiplication with the help of a calculator. The accuracy of the calculation is not at issue.
The issue is that the multiplication is not valid according to Bayesian probability analysis. It doesn't matter how valid the original numbers are if you interpret them incorrectly. The implicit appeal to authority is that a group known for social policy commentary is somehow expected to have greater credibility in the area of statistical analysis.
In reality, they are just as bad at it as everyone else.
So in exposing the appeal to authority, we see more clearly that the burden is on them to show that their analysis is mathematically correct. So tell me. Why does the multiplication support their claims?
Scroll up. I'm not claiming white people should be afraid of blacks. I'm claiming that they have a vague proximal reason to be afraid, analogous to maaku's "possibility of being assaulted without recourse or lynched...a few generations back".
My opinion on all of these vague feelings of fear: "completely irrational and entirely his [the person feeling it] problem."
It's generally quite easy to do so when the source of information is biased, so dismantle the message if you want to argue about how it's incorrect.
It looks like these numbers posted were very low effort and lacking any real context whatsoever, so it shouldn't be too hard to rebut them.
Edit: In fact, unprepare does so quite well in https://news.ycombinator.com/item?id=10655743