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I have a residual plot which is shown below and I am not sure if the variance is constant or not because I can see a funnel shape. Could anyone help me to make a decision about thatresidual plot

Could you please suggest me a test to make sure that the variance constant or not constant

shahd
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1 Answers1

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You might do better to plot the scale-location plot. So instead of plotting the residuals against the fitted you plot the square root of the absolute value of the residuals against the fitted. If you do that then increasing variance is shown if the values increase towards the right (or more rarely the left). You can plot a smoothed line through the points as well, like loess, which can help the visualisation.

mdewey
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