A Probabilistic Based Failure Model for Components ...

3. If the coefficient of Z is 0 then the model is homoscedastic, but if it is not zero, then the model has heteroskedastic errors. In SPSS, you can correct for heteroskedasticity by using Analyze/Regression/Weight Estimation rather than Analyze/Regression/Linear. You have to know the variable Z, of course. Trick: Suppose that t2= 2Zt2. ................
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