anova

  1. A

    how to analyze data with 3 samples with factorial experimental design

    I am trying to analyze data for my thesis so a factorial experimental design has been suggested. The problem is I have done the collecting data process before designing such an experiment. I have just 3 samples with 6 factors (velocity, time, depth, humidity of soil, humidity of environment) and...
  2. M

    ANOVA after logistic regression?

    I have fire incidences data with variables - seasons (summer & winter), time taken by fire truck to arrive (Early (<30 mins) and Late (>30 mins)), area (area code), small fire incident (1=Yes, 0=No), and big fire incident (1=Yes, 0=No). It has multiple observations recorded from multiple...
  3. M

    t test or ANOVA for my survey results?

    Hi all. I ran a survey where I showed 2 ads to men and women in 5 different countries to see which they preferred. I want to know if gender or country influenced the selection of a particular ad preference. The data is normal. I was told to use a One-way ANOVA but I don't think this is correct...
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    I have a 2x2 crossover design comparing 2 treaments but don't have a clue what statistical analysis to use in SPSS

    I have a 2x2 crossover design comparing 2 treaments with a washout period in between but don't have a clue what statistical analysis to use in SPSS. I am not that good at statistics since it is not my trade. I measured at baseline prior to starting treatments on subjects. When they finished...
  5. H

    Identifying correct statistical test for comparison of two groups related to time

    Hi, I'm conducting research into woodlice grouping behaviour. I have tested three conditions that are full darkness, full light, and a half-dark, half-light group with each having a total of three replicates. For the full darkness and full light conditions, I measured the frequency of...
  6. O

    Study design

    If I’m doing an fmri experiment with two between-subject factors (two treatment groups) and 3 within subjects groups (baseline, post-treatment, follow-up. Which design is better a 2 x 3 ANOVA flexible factorial design, or a two way mixed effect repeated measure? Thanks!
  7. R

    ANOVA for Sampling bias detection

    I hope that this is the right place for such a question. What test to use to detect if the selected sample has a bias or not? We have a protein that naturally binds with certain short known DNA sequences (let's say 5 nucleotides each). what I want to show, is that from all possible...
  8. B

    F test significant but simple contrasts not

    Hi All, I have conducted a repeated measures ANOVA, examining one of my dependent variables over 5 time points. I have a significant main effect from my F test but not when i am examining my simple contrasts (see images below). Could anyone offer any advice on why this is and what should be...
  9. B

    Post-hoc pairwise or simple contrast ANOVA

    Hi All, I am examining a dependent variable over 5-time points but what I am really interested in is how the dependent variable differs in comparison to the first time-point (baseline). Firstly, which ANOVA is more appropriate, a repeated measures ANOVA with post-hoc analyses or a simple...
  10. R

    Comparing Groups - Are my stats tests biased?

    Hi, I am testing for statistical significance between lipid (oil) yield of two separate algal species split into four groups total. Each species has been split into two treatment groups, one with fewer nutrients and one with more. Therefore I have four groups to test statistical differences...
  11. L

    How to convert my output into a suitable table for ANOVA or Kruskwallis testing on SPSS?

    Hi guys, Let's say I have asked an individual to classify images according to 3 fruits that he sees : apple, banana and kiwi. Then, I want to assess whether there are significant differences between the frequencies of each classified fruit (there are more instances, this is just an example). I...
  12. Z

    2*2 repeated measures ANOVA with an unbalanced number of observations

    Hi everyone, sorry for this very basic question. I've trawled through previous pages and cannot quite find a case that corresponds to our situation. 320 individuals rated two types of films. The rating was provided on a 1-11 scale.There are many films of each type. In short the DV is a...
  13. K

    Why three-way ANOVA doesn't match with multiple comparisons?

    Hi, I'm running a three-way ANOVA on a multifactorial dataset and it says all three (Device, HRT, Dose) variable has a significant influence on the data. However, when I run multiple comparisons, groupings and significance appear only based on one of the variables (Dose). Why is that and which...
  14. B

    Grade data - difference among graders

    Hi, I have 6 groups of grade data, scored by 6 different graders. I want to know if there are statistically significant differences between graders. Each score was earned by a different student. There were 72 students in all. I ran an ANOVA, but am not sure if that is the right approach...
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    Are transformations appropriate for my dataset?

    Hi all, I have a question about transforming data before running a 4-way ANOVA: I want to run a four-way ANOVA on my data set (factors: BWWW). However, due to the nature of one of the between-factors, a ceiling effect is reached in most of these data subsets, but not all. This means that the...
  16. P

    Confused about what type of ANOVA is required

    I'm doing a study for university which involves a series of participants (about 150), undertaking a study with 3 conditions and a control condition. The participants are all of different ages and are both male and female (though not an equal number of each) and all participants see all...
  17. A

    Within-Subjects ANOVA with low sample

    Hello, I have some data that I want to analyse. It is 2x2 within-subjects design. My DV is continuous and the two factors have 2 categorical levels. But I only have 8 subjects, so I am unsure about how to proceed. Is it correct that there is no reasonable alternative to just using an ANOVA? If...
  18. P

    2-sample t-test shows no equal means, can I still compare capabilty analysis and Ppk's?

    I want to compare two categorical situations (old vs. new part in a machine) with the continuous CTQ, the y-variable. In order to compare the 2 situations, I found the proper distribution and compared the two Ppk values. I saw a significant difference in performance (the new part was +-3 times...
  19. J

    degrees of freedom with a mixed anova design

    Hello - I am trying to figure out why my degrees of freedom are decimals rather than being whole numbers. I am running the mixed anova in R and the assumptions have all been met. The sample sizes of the two groups are unequal. Would this be an explanation? Or could it be that there is a...
  20. P

    Manova, Hotelling's T^2, t-test or Anova?

    Hello, For my final thesis, a few questions arose during the pre-registration process and I would be very happy to receive answers. I will conduct an experiment with three groups (1, 2, 3) and 3 dependent variables (a, b, c) to find answers to the following 2 hypotheses: H1: M(2) > M(1) -...