t-test

  1. I

    Likert scale analysis - ordinal or interval??

    Hi, I would appreciate some help so much as I feel I am going round in circles with every journal article I read! So I am currently trying to analyse the survey responses for my dissertation based on a 5 point likert scale. I gave surveys to two groups, a control and an intervention group...
  2. S

    Paired samples t-test for an interaction

    Hi all, I'm currently writing up my final project for university. The general idea is testing the role of language on emotion perception in faces, with the hypotheses being that emotion words will facilitate more accurate perception of emotional faces than do neutral words (i.e. more correct...
  3. C

    What Kind of Test?

    Hey guys, I was wondering what is the best type of test for this: I'm investigating vegan identity. I have calculated an "integration score" for each individual and am seeing how factors affect that. I want to see how familial support affects the integration score of females only. Would this...
  4. M

    Anova or t-test on squared errors

    I have two forecasting models, moving average and single exponential smoothing. The values of Mean Absolute Percentage Error (MAPE) is 5.2%, 5.8%. Since the difference of MAPE between the models are very close, I am quite confused which model to choose. Can we perform a t-test or ANOVA on...
  5. D

    Justification for t-tests instead of 2-way ANOVA (no interaction)

    HI there, I need help with justification for why I should use a t-test instead of a two-way ANOVA. My two-way ANOVA gave me a main effect of Diet (ethanol and control) and a main effect of Drug (drug and no drug), but no Diet x Drug interaction. Since there is no interaction, I don't feel...
  6. rukia

    Independent T-test or ANCOVA?

    Hi everyone; Hope you're doing well!! I'm conducting a PhD dissertatind in educational research, I made a test to compare some students performance but I've got lost since am very bigginer with statistics :confused::confused:! So here is the problem: I've made a 2 tests to comapre a control...
  7. N

    Need help with testing for significant differences

    Hey all, it would be very nice if someone could help me! I want to test for significant differences in a dataset where I have 4 different locations for which I assessed the total weight (kg). So I have A-1 (kg), A-2 (kg), B-1 (kg) and B-2 (kg). I subdivided those then into different...
  8. F

    Help needed to check statistics in thesis

    I would really need someone to check my stats work for my thesis, as I am not entirely sure about what procedures I carried out. Quick overview of my my experiment: - I investigated 2 methods of using worked examples to study the division & multiplication of fractions in 2 year 7...
  9. 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...
  10. U

    Different results by adding a third group?

    Hi, In my study I first only compared two different groups (1 and 2) on a number of variables. For one variable in particular, these groups were significantly different from each other (found that on t-test and ANOVA). Now I added a third group to the sample. In each of the groups N=21...
  11. S

    [R] Prevalence by site. Stuck after fisher.test and pairwise.t.test

    Hi, I run into a problem I can't solve and I got stuck doing the pairwise.t.test. I'll try to give you as many details I could so maybe you can help me out. Thanks in advance. I'm studying the prevalence of one parasite on a host from different localities. I do it by assigning presence...
  12. M

    How do we avoid pseudoreplication while examining stickleback-gender in perch stomach

    We are working on a project were the sex of sticklebacks in perch stomachs are assesed. The question here is; how do we avoid pseudoreplication? We want to find out if there is a difference in consumption of the different sexes AND we want to find out if the ratio differs from the sex-ratio...
  13. E

    Confidence Interval

    In 22 patients with an unusual liver disease, the plasma alkaline phosphatase had a mean value of 39 IU/l (International Units per liter), standard deviation = 3.4 IU/l. Calculate the 95% confidence interval for the population’s true mean value of plasma alkaline phosphatase. My equation...
  14. S

    Dissertation Results Comparisons - which SPSS method should I use?

    Hi everyone, I'm in my final year as a Psychology student aspiring to be a cognitive neuroscientist (accepted to birmingham university provided I get my 2.1 class honours :D), firstly I'd like to thank you for your time to read this (especially since there is a lot of reading to be done, I...
  15. F

    Which test would be appropriate to test multiple variables?

    I have a data on users with 5 personality variables. The users had to pick a logo for three different projects (most likely, may be, least likely). The question is why the users chose the logo they did - is it the color, the shape, etc. There are 3 data sets - the personality test results...
  16. E

    Is t-test appropriate for comparing percentages?

    I am trying to analyze a seed germination trial comparing 2 different germination treatments. I sowed seeds from 10 individual plants in 10 different petri dishes for each of the 2 treatments, with between 22 and 200 seeds per dish, and recorded germination rates (number of seeds germinated per...
  17. R

    How to check whethere there is a difference between 5 samples means

    I have five samples with their means (60, 58, 61.5, 48 and 42) and standard deviations (1, 3, 1.5, 4 and 2) for 3 trials. How to check whether there is a significant difference between these values by statistically.
  18. K

    Comparing Groups 2 sample T-test or Anova

    So I have a word problem that I can't get my head around. Perhaps because the wording of the question is leading me down the wrong path about the variables. Any help would be greatly appreciated. So we have two variables (dissolved oxygen and levels of chemical waste) both quantitative. So...
  19. S

    Required sample size to distinguish means of two binomially distributed rv

    Hello, Currently trying to work out the best way to calculate the number of samples that would be required to get a certain confidence interval. If I have two binomially distributed data sets, which I predict to have some probability of an event p_1 and p_2. If I were to estimate p_1...
  20. E

    Follow-up tests with 2-way within-subject repeated measures ANOVA

    Hi everybody, I've been doing a 2-way within-subject repeated measures ANOVA and I have some questions: 1) Is it correct that I'm only allowed to do follow-up tests if I see an interaction? 2) Is it acceptable to do t-tests as follow-up tests or should I use something else? Best...