Easy: Determine Main EffectsAfter a full factorial design was executed I have the following tabulated results:
Force | Pressure | Hours to failure |
15 N (Low) | 10 Pa (Low) | 2800 hours |
15 N (Low) | 150 Pa (High) | 1300 hours |
100 N (High) | 10 Pa (Low) | 800 hours |
100 N (High) | 150 Pa (High) | 300 hours |
How would I determine the main effects of Force and Pressure? I've added this data to a table, my next move would be to Analyze > Fit Model and figure out to make a Least Squares Mean Plot. Having a hard time setting that up in the Fit Model.
Design of ExperimentsMass CustomizationSharing and Communicating ResultsRe: Easy: Determine Main EffectsI stand corrected.....
Re: Easy: Determine Main EffectsUmmm, yes there are. I always start with a saturated model, use Normal, Bayes and Pareto plots as well as look at parameter effects and SS. Use engineering knowledge and predictions about potential effects to then reduce the model. I really don't place much weight on p-values as YOU control these via how you collect your data. So, for example, if you leave the interaction out of the model, guess what...the interaction is the estimate of mean square error and is therefore the basis of the statistical test (F-test). For unreplcated designs, I much prefer the unbiased Daniels plots, but that's just me.
Re: Easy: Determine Main Effects@statman
Not enough df
Re: Easy: Determine Main EffectsEric, welcome to the community. Jim provided the steps to do exactly what you want. I would simply add...why not also get the interaction effect while you're at it. 3 total DF's P+F+PF
Re: Easy: Determine Main EffectsEnter your data into a data table
Go to
Analyze=>Fit Model
enter in the model you want to analyze
And click OK
Re: Easy: Determine Main EffectsYep, you got it!Re: Easy: Determine Main EffectsDid you only measure one Hours to failure for each combination of Force and Pressure?
