factorial anova

  1. J

    2 Way ANOVA or multiple t tests with correction?

    Hi all, I am trying to do some data analysis, and I'm not sure whether to use a 2 way ANOVA or multiple t tests with Bonferroni correction. I am looking at the effect of a chemical on bacterial binding to different polymers. So for each polymer, I want to know if there is a difference in...
  2. R

    Factorial ANOVA, How to do a imple effects analysis in R?

    I am running a factorial ANOVA in R. I want to find out the effect of gender and the semester the student is enrolled in on a standardized test. It is a factorial ANOVA design with two independent variables: gender (M,F) and semester when the student takes the test (1:12). The dependent...
  3. S

    Quick one please: Difference between 1-way and 2-way ANOVA - Example provided

    Hello, I apologize in advance if this is too simple for these forums, but I am just wanted to be very sure. Example: A study that looks at 2 sleep treatments and their effect on 1) how long they think they slept, 2) how rested they feel, 3) how alert they are, 4) how good their sleep was...
  4. W

    (R) Analysing abundance in plots with different treatments -with factorial ANOVA?

    I'm not connected to a Uni anymore, but want to write an article on my friend's data from her Master's while applying for a Phd. The data will contain 2 analyses of vegetation growth in different plots exposed to different treatments (+control). The plan is to use the sum of the plots. The...
  5. H

    Transform data for factorial two-way ANOVA/General Linear Model??

    Hi, I'm not very statistically minded but I would really appreciate some guidance. I am needing to do several stat tests for my MSc dissertation. I have one dependent variable (species count) and one independent variable (year), but two species. I have constructed a basic count against year...
  6. M

    What would you do if you had two very different Values of Cohen's D?

    I conducted a factorial ANOVA.. and I found a significant interaction. I used two independent samples t-tests to conduct a further simple effects analysis one group always had higher accuracy than the other group regardless of the condition. However: condition 1 had an extremely...
  7. J

    Determining sample size in a factorial repeated measures ANOVA using GPower

    Hi all Can anybody tell me which F-test option in G power 3.1.9.2 is appropriate to find out the sample size for a 2x2x2 repeated measures ANOVA? The three within subjects factors are A, B & C. I am interested in finding out how many subjects I will require to find a main effect of A...
  8. M

    repeated measures factorial ANOVA post hoc test

    Currently I am working on a way to distinguish Delirious patients from patients who still suffer from anesthesia and controls. I use the EEG and calculate relative powers in four frequency bands (Delta, Theta, Alpha and Beta) in three different regions (Anterior, Central and Posterior) of the...
  9. C

    ANOVA - Orthogonal Planned Comparisons

    We've been given this question on a sample exam paper. An experimenter is exploring the effects of two appetite suppressants in rats. Suppressant A induces mild nausea, while Suppressant B suppresses the sensation of hunger. Half the subjects receive a low dose of one suppressant, and half...
  10. L

    which type of ANOVA?

    N mineralisation is dependent variable. Management type (4 types) and position in valley (3 positions; nested in valley (with valley nested in management type [is this possible?])) are my independent variables. I want to test the affect of management type, position and interaction of both, on...
  11. N

    ANOVA One-way Vs Factorial ANOVA. Discordant results. Help

    Hi everybody, I have to investigate the influence of many categorical factors (A,B,C) on a continuous response variable (Y). The procedure I'm following is: 1) Make three One-way ANOVA, every time with a different predicotor A, B, C) 2) Make all the three possible ANOVA two-way using the...
  12. R

    linear correlation between T values and coefficients for two-level factorial designs

    Hi all Since I'm not sure if it is a problem of Minitab or not I decided to post this question here. I'm new in multivariate statistics and I would like to understand a possible "linear correlation" between T values and the model coefficients in two-level factorial designs. The problem is...
  13. R

    Implementing non-parametric version of 2x2 Repeated Measures ANOVA in R

    Hi, I have a 2x2 repeated measures design (i.e. 1 group of participants provide data for all 4 conditions in a fully factorial counterbalanced design [so there is no time factor to worry about]). The data is non-normal so I need to use a non-parametric equivalent of the 2x2 factorial ANOVA...
  14. H

    Moderated Multiple Regression versus Factorial ANOVA.

    I am analyzing an interaction effect between two continuous independent variables (Z and X) on a continuous dependent variable (Y). I have conducted both, a moderated multiple regression analysis and a two-way ANOVA (spliting each predictor at its median), obtaining different results. Using...