design of experiments

  1. M

    Constrained design of experiments

    Good evening! I would like to conduct a 2-level fractional factorial experimental design on 8 factors. I used the FrF2 package in R to do so. I have capacity to do roughly 30 experiments, so I selected a resolution IV 2^(8-3) with one center-point. Repeats aren't necessary for reasons related...
  2. E

    Quasi-experiments and variable manipulation

    Hello, I am new here so forgive me if I seem amateur, After doing a lot of research and discussion with other students I have continued to find conflicting information about whether the manipulation of variables is or is not required in order for it to be a quasi experimental design. Can...
  3. S

    Factorial experiment in CRD with unequal replications

    Hi guys, i am a graduate student in statistics. i want to test for the main and interaction effect of 3 treatments on a group of patients. let say i have treatments A, B and C. each with 2 levels, presence and absence. So i decided to perform a 2^3 factorial Experiment in a Completely...
  4. N

    Repeated Measures - Maximum number of variables

    I know that the general rule of thumb is that you need 10 observations or 10 cases per variable in your model. How about in a repeated measures model? Do you count the clustered data as one observation or would you count each measurement as an observation in determining the maximum number of...
  5. T

    Is this Experimental Design even possible? Help please!

    Hello all, First thank you in advance for any and all help given in response to this question. I've been searching this forum as well as other places online and I'm still confused about what methodology I should use in this experiment. DESIGN: Participants are given two questionnaires...
  6. 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...