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- Reading a qqplot in an example, I find that the graph in question doesn't match with the conclussions. Can anyoe please confirm this?

Hello everyone. I am currently reading a book on quality control. In the part of experimental design, here, the effect vector, beta, takes the following form: beta=(81.75, 9, 0.75, -4, -0.5, 0.25, 3, -0.25), which corresponds to the effects of lenght, width, type of steel and their interactions, LW, LT, WT and LWT. The book then present the qqplot to determine the significance of each one of the effects. All the terms of beta but the first are present, that one is the mean effect (see attached image).

Then, the analysis of the graph goes as follows: L and LWT are significant, LT is on the fence and the rest are not.

My question goes as follows: The elements of the vector beta don't appear in order on the qqplot, however, the book treats them as if the first element of the vector is the first element of the qqplot (L) and so on. Is my book right or does the graph shows the elements of the qqplot on a different order that they were at beta?

Thanks for your anwser.

Then, the analysis of the graph goes as follows: L and LWT are significant, LT is on the fence and the rest are not.

My question goes as follows: The elements of the vector beta don't appear in order on the qqplot, however, the book treats them as if the first element of the vector is the first element of the qqplot (L) and so on. Is my book right or does the graph shows the elements of the qqplot on a different order that they were at beta?

Thanks for your anwser.