Q (Gelman):

I don't understand what's going on. What's the x and y-axis?

A:

Okay, so once again, the x-axis here is just the score of the demographic space, so that's my predicted score.

Q (Gelman):

The x-axis is labeled Bayes prediction, not expected value of the data.

A:

So, remember what the model is, it's is equal to plus gamma demographics plus random error, so the point is, that, what I want to do, I've got twelve demographic, or eleven demographics here, so I could show you like eleven plots for eleven demographics variables, and instead what I'm doing is I've just given you a plot of against this gamma demographics. So, the point is just trying to regress it against, my y against my . But the point is, that the least square estimates don't necessarily have to have any relationship, so my least square estimates is not , it's my Bayes estimates that are . So, obviously you're going to see this relationship between the Bayesian demographics but it's not clear that your going to see this with the least square estimates in the demographics.

Q:

So the reason why the black diamonds fall near the 45 degree line is these store effects which are on the y-axis?

A:

It's these random effects that are going on. So, it's just a way of trying to illustrate, well, what does this stuff look like?

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