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DS4PS / cpp-523-fall-2019

Course shell for CPP 523 Foundations of Program Evaluation I for Fall 2019.
http://ds4ps.org/cpp-523-fall-2019/
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Statistical Significance? #6

Open jmacost5 opened 5 years ago

jmacost5 commented 5 years ago

I want to make sure I am understanding this correctly. I saw that the p value on the table for all of these was p<0.01 which on the table I saw that this was from *** icon. That makes all these values statistically significant correct? For the final problem I was confused because I know that you can use covariance and var(x) to calculate the slope of a regression but I was wondering if I did not think hard enough about the problem and I was actually wrong on my thought process.

lecy commented 5 years ago

(1) Correct, the tables do not report the p-values directly but they do include stars. It is good to note that regression tables can report (a) standard errors, (b) t-values, or (c) p-values in parentheses so it's important to pay attention. Here it is standard errors, so stars represent significance.

I would take another look, though, at the table. Class size should not be significant in all models.

(2) The first assignment was a bivariate regression (one independent variable only ).

This is a preview of the lecture next week on control variables. If you calculate the slope from the cov/var equation, can you find that slope somewhere on the table? So when can we use this equation?