doe

  1. G

    Analysing 2-factor 2-level design as if it were 4 different treatment design

    Hello! Just curious why we see different results in such cases. Here we have a classic 2-factor 2-level factorial design which we can analyze using Nominal regression/logistic regression. Analysis shows that only interaction is significant : However, if we transform this data as if there...
  2. A

    Defining relation of a fold over design

    Dear All, I am reading the book DC Montgomery on my own. The book says that the defining relation for a foldover design will have L + U - 1 words used as generators where L = number of words of like sign, U = number of words of unlike sign. Here U-1 = number of independent products of words...
  3. rogojel

    Interpretation of a one - way ANOVA

    hi, I am working through a designed experiments texbook and I would like to see if I got one exercise right. The story is about measuring the effect of baking powder on the height of biscuits. The exoerimental factor is the amount of soda with, say, 3 levels - let us call it low amount, medium...
  4. R

    [Minitab] DOE Model Output vs. Actual Data

    I am running multiple 3 factor DOEs and each one of my model outputs fits very well, all above an 80% fit. The problem I am having is that when I plug our recorded values into my model for parameters x,y and z my model outputs a significantly different/unfeasible value when compared the the...
  5. I

    Which approach to use for designing my experiments (DoE)?

    Hi all and welcome to my first post. I am new to the field of DoE and did a lot of background reading. Now, I need to design a series of experiments: I want to fabricate a specific part on a machine and investigate the influence of about 15 factors on the mechanical strength of that part. Some...
  6. J

    Statictical suggestion regarding DOE and GLM for the pharmacutical related problem

    We performed a DOE to study the relationship between simulated intestinal fluid (SIF) components and solubility of drugs. The DOE is composed of 7 factors (representing the components of SIF) and 2 levels for each drug. And we have done several drugs with the DOE. Now with the DOE analysis, we...
  7. D

    Help with Minitab Taguchi aplication

    Hello, I have a question about using minitab DOE Taguchi design aplication. When I have a three factor theree level (L9) Taguchi design and apply Minitab for the analysis I have a problem to understand the results of analysis for the coefficients Term Coef SE Coef T P...
  8. D

    Definition of replications vs treatments (factorial design question)

    I see on wikipedia replication is "the repetition of the set of all the treatment combinations to be compared in an experiment. Each of the repetitions is called a replicate" but I think of each combination of factor levels as different treatments, how are these different? If there is a 2^2...
  9. D

    DOE for rock paper scissor analysis - suggestions for analysis needed!

    Hi, I am in a design of experiments class at my university. We are analyzing rock-paper-scissor strategies and results among females and males on our campus. We gathered our data by grabbing 1 group at a time of 2 random males and 2 random females walking around campus and had each of them play...
  10. L

    [Statgraphics] - Effects of a parameter and Optimization of Response do not correlate

    I perform an analysis on DOE and as it can be seen on the attached pictures, the effect of Pressure on my experiment is supposed to be negative (less oil obtained the higher the pressure) However, when checking the optimization given by the program to maximize the Oil, the value given for the...
  11. R

    Fractional Factorial Design Question

    Does anyone have experience with using fractional factorial designs for psychological research? I'm new to DoE, and I have no guidance except the internet... not too helpful. Anyhow, I have a practical question about data collection and entry (e.g. minitab) The question is: if I have...