Minitab DOE Tutorial interpretation

Step 4 validating anova assumptions as stated in

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Step 4. Validating ANOVA Assumptions As stated in Example #1, there are three assumptions in ANOVA analysis: normality, constant variance, and independence. The normality plot of the residuals is used to check the normality of the treatment data. If the distribution of residuals is normal, the plot will resemble a straight line. The constant variance assumption is checked by the plot of residuals versus fitted values. If the plot of residual vs. fitted values (treatment) does not show any pattern, the constant variance assumption is satisfied. If the plot of residual vs. run order (time order of data collection) does not reveal any pattern, the independence assumption is satisfied. It seems that there is nothing unusual about the residuals in Example #2. P value None of the P values was below 0.05. Thus, we cannot reject the null hypothesis, which is the lead-free solder joint shear strength of 0402 is same at different reflow profile.
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