Hello:
I created a 2^3 full factorial experiment with 4 center points. X1, X2 and X3 are the factors and Y is the response. X2 and X3 are just any random factor, but X1 is the radius and Y is the area. So mathematically relation is Y=3.14*X1^2
Below are the three scenarios where I computed regression equation based on just X1, both X1 and X1^2 and only X1^2.
When I only consider X1^2, it is no more significant. On further researching I came across Effect Heredity which states that we should have lower order effect included when we have higher order effect in our regression model. But than we will never be ale to find a relation that is pure quadratic as in this case.
I have also mentioned the model details that I used to analyze the data. Does different setting give me a better answer.
Please let me know if I have a serious flaw in my understanding and am doing a very basic mistake in understanding DOE.
Your help is highly appreciated.
Best Regards,
Varun Katiyar
