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I am doing some multivariate regression. When I plot QQnorms to check my model assumptions (errors normally distributed), I get enter image description here

Question: How do you interpret the above? Are the normality assumptions completely off? What's with those "breaks" near the ends of some of the plots? Is this caused by outliers?

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marked as duplicate by Glen_b Mar 22 '17 at 6:42

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  • $\begingroup$ Look at this answer for how to interpret visual aspects of qq-plots. But are you sure that, with the way you got these plots, you were comparing the residual distributions against a normal distribution? Looks like you might be comparing among variables against each other. $\endgroup$ – EdM Mar 22 '17 at 0:41
  • $\begingroup$ Given some people plot QQ-plots the "wrong way around" (to my way of reckoning), you should be clear about which axis is which $\endgroup$ – Glen_b Mar 22 '17 at 3:10
  • $\begingroup$ If the indicated duplicates aren't sufficient to answer your question, please edit your question to ask about the specific issues not covered in the linked answers $\endgroup$ – Glen_b Mar 22 '17 at 6:49

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