#MINITAB 18 DEGREES OF FREEDOM HOW TO#
#MINITAB 18 DEGREES OF FREEDOM SOFTWARE#
#MINITAB 18 DEGREES OF FREEDOM SERIES#

However I find the output fairly useless since: I guess there is something wrong with the model itself.ДЄlso I tried using the Gauge R&R in Minitab. Ok, I tried using Repeat(Cycle) this still yields the DoF error. Therefore the assumed statistical model is: Each day the wafers were loaded twice in random order and measurement performed twice per load cycle.

#MINITAB 18 DEGREES OF FREEDOM SERIES#

It is a thickness measurement series on 5 different wafers (with very different thickness values) that was performed on 8 days. The data is taken from an example - supposedly from real life with a bit of adjustment to make a point. Does Minitab have a limit in display accuracy depending on the order of magnitude of the terms? What about the large residual in Minitabs calculation - I guess this will relate to the second question? Where did the variance for the component Day go? ( Well I know it vacation time, yet. Why exclude Cycle in the model as a factor for repeat to be nested in? The value is several orders of magnitude higher than everything else - as is to be expected in an MSA when the system is tested in the expected process range. One problem I see is the huge wafer to wafer variance that seems to throw off Minitab a bit. However the Day component is missing and the residual is quite high!? well with lots of rounding error it has a similar magnitude. So the correspondence for the Wafer by Day interaction is quite good. Variance Error Expected Mean Square for Each Term If anyone can point me into the right direction on this I would be more than grateful! Unfortunately I have found nothing on the web, the help files or this forum yet.

The only way it seems to work is when I drop the factor repeat completely out of the model.* However, I do need to get this component somehow. Ok having done all this I get the following error message: The data is balanced and arranged as required (it worked for other tests with the premade MSA analysis).

Options: use restricted form of model - no

Model: Wafer Day Wafer* Day Cycle( Day Wafer) Repeat( Wafer Day Cycle) Repeat(hkji).effect of i repeats nested in cycle, wafer and day Wd(hk).effect of wafer by day interactionД¬ycle(hkj).effect of j cycle nested in day and wafer Wafer(k).effect of k wafer values (its a thickness) Thickness(hkji) = mu + day(h) + wafer(k) + wd(kh) + cycle(hkj) + repeat(hkji) + e(hji)

Having failed with the premade analysis options in Minitab (the part-to-part variance is killing the results!?) I went back to the old fashioned way of just doing a balanced ANOVA and entering all the factors and terms myself. I am using sample data from SEMI E89 RI 4 and am trying to repeat the analysis as it is described in there with Minitab.

#MINITAB 18 DEGREES OF FREEDOM HOW TO#

I did some tutorials on how to use MiniTab etc. I know what a balanced ANOVA is and what a model is and how it should be written.

#MINITAB 18 DEGREES OF FREEDOM SOFTWARE#

I am new to MiniTab Software and familiar with basics of statistics. * ERROR * Zero or negative degrees of freedom. When doing a balanced ANOVA I get the error:

Minitab 18 degrees of freedom