why square $r$ what is the variance of the r value in a regression model? why do regression models give the figures of explained variance? why would square r$ in regression why sqr $r$ why squared $r$ for explained variance why square r$ in regression why sqrt regression model why are regression coefficients squared to give a figure of explained variance? why do you square r in a regression test why square r$ and give the answer of explained variance why square the variance of $r$ why is $r$ a square in a regression model why squaring r$ gives explained variance? why does square r$ give variance why resquaring r$ gives a figure of explained variance? why squaring $r$ results in explained variance why square r$ why square $r$ in regression model what would be the a value of the r$