> I.e., banks choose who to extend loans to based on non-racial factors like debt/income, job tenure, home appraisals and models of future home value? Yep, nothing voluntary at all about a private party choosing who to trade with.

The fact that those factors are non-racial does not mean it's not racism! We're back to that again. Racism (like sexism) does not require malice or ill intent (or even bigotry or prejudice) once its systemic! Suppose you make sure by some way that there's a strong correlation between race and wealth, and then a bank gives loan only to rich people. Well, that's racism! That doesn't mean the loan officer is a bigot! This is something you need to understand. Banking practices can be racist even if no one at the bank is prejudiced (they can all be liberal Democrats who voted for Obama, twice), and all of their decisions are based on pure financial reasons, only because hundreds of years ago society was organized in some particular way. That's how it works. In fact, you could say that everyone is a victim, because those bank officers, through no fault of their own, are now cogs in a racist machinery. So they're victims, too, except that some people are bigger victims than others -- some are part of a racist system, and some feel its consequences every day.

If you, by some mechanism, create a society in which people's rational, self-serving actions would result in a system where power is largely withheld from some racial groups then you've built a racist society even if no one in that society is a xenophobe.

> which is about people choosing which houses to buy based on tribalist feelings.

No. "Based on tribalist feeling" is your conjecture. Yes, tribalist feelings are probably a contributing factor, but racism is a much more dominant one. How do I know that? Well, because I bothered to read some studies.

> Asking concrete questions is "nerd bigotry"? Um, ok. I'm not even sure what that is, but asking makes me just a creationist so meh.

No. Pretending to ask question you don't really want the answer to, and ignoring science because it isn't physics is.

In fact, there are a lot of interesting questions an interested nerd could ask. For example, while anti-nerd discrimination is certainly not systemic, one could ask about discrimination against unattractive people. I think there are studies that show they are being discriminated against even on loan applications (and from there you could take it to other correlations and discrimination by proxy etc.). Of course, it's not too hard to show how that's not at all like racism or sexism (if only in measure), but at least there is something interesting to talk about. That would be a college-, or even graduate- level question. But your "questions" are kindergarten level, and show that you have no desire to even learn the very basics of this issue.

> See how appeals to unstated authority are not productive?

My uncited experts can be found in a 2 minute Google search. Yours are made up so I win.

> If this were an HFT discussion, one of the HFT's would have just linked to a page on nasdaq.com and said "go read the docs on hide-not-slide orders, you'll see they work like I just described".

Wow, those guys are really smart! I won't send you links to the top 50 papers showing the data, or even to the top two, because either you won't read them, or, if you do, you'll make up a baby-nerd argument to invalidate them because the definitions (which, as always, would rely on you having some basic background in the science) won't be rigorous enough to your liking (because you don't have the background). Then, I'll send you links to books with the definitions, which you won't read, and it will end up just you asking me to teach you all of psychology and history back to first principles, which you won't find satisfactory until I go back to elementary particles, which is impossible because we're dealing with intractable science (and hard because I'm not knowledgable enough). So, no thank you.

Also -- and that is the real reason you find HFT discussions different -- this kind of discussion evokes a response in you that makes you unwilling to open yourself up to new information. HFT doesn't. Yes, just like a creationist; I'm sorry, but it's the same kind of emotional response, only you and the creationists reach for your own kind of weapon -- yours is misused logic. I mean, you know all those thousands of studies exist (I'm sure you've seen those buildings at your university), and you know everyone who has studied them reaches similar conclusions (similar enough for you, that is; there are quite a few controversies), but you choose to believe that those conclusions are based on faulty logic rather than on data (they are based on data), and you think you can argue with them using logic (logic, BTW, is not so effective in the intractable sciences, just as it's not so effective in QM -- until you learn the basic mechanics of things). Those conclusions are the result of 40 or so years of research by thousands of historians, social workers, sociologists and psychologists. Some of them -- though not all -- are great scientists.