t test

  1. 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...
  2. P

    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...
  3. victorxstc

    Nonparametric alternative to point-biserial correlation coefficient? - Which? t-test or Mann Whitney?

    A. I know from the net that for a design with one binary variable and a second variable that is continuous but is NOT normally distributed, I can use BOTH the point-biserial correlation (which is basically the parametric Pearson correlation formula) as well as the Rank Biserial Correlation...
  4. E

    What is the best T test to use for my data?

    Hi, I'm trying to work out the correct non parametric T test to use for my data. My data is made of two large groups. Each value in the first group has a corresponding later value e.g. it is showing the chance in frequency from point 1 to point 2 over time, there is many different points for...
  5. D

    One sample t test

    I have a population of 11 samples. Can I take the mean from 2 of those 11 samples and use a one sample t test to determine if the mean of the 2 samples differs from the 11 sample population? Is there a better method? Thank you
  6. M

    Choosing a method for a two-sample statistical test

    Hello everyone, I am trying to find a best method to analyze the difference between two datasets. The thing is I have a separate software where I calculated environmental impacts from production of a certain chemical substance. However, not all information was available about the actual content...
  7. M

    Statistically Significant Data for Test Engineer

    A common engineering experiment is to test something until failure to determine its ultimate break strength. Sample sizes can range from 5 to 100 pieces. I would like to know what statistical tests are used to make sure the data is good. Statistical tests that I am aware of are used to...
  8. C

    What test should i use? THESIS HELP!!

    Hi, I am currently studying Zoology at university. I am currently in my final year conducting my dissertation. I have completed my data collection and I am now on to my statistics. My dissertation looks at the relationship between light intensity and growth rate in marine sponges. I have 5...
  9. D

    Statistically significant difference between distributions only knowing the mean and std dev?

    I have 3 specimens (A, B & C) and 5 sets of observations from A & B but only 4 from C. Each observation has been reported as a mean & a standard deviation. I do not have access to the underlying data. I am curious about whether the samples are statistically different from each other as far as...
  10. E

    Statistical significance of results

    Hi, I made an experiment and I want to know if the results are significant or not. But I know nothing about statistics. In that experiment, I show a serie of 70 videos to 12 participants. Each participant should select from a list of seven choices (the same for all the videos) the emotion...
  11. F

    Testing help

    Hi all, Not sure if any one can help but here goes. For a recent research i carried out a survey on moths. I picked 2 separate areas, wooded area and a totally different area habitat wise. Area "A" and Area "B" For each area i mapped out 10 unique collecting sites. I then carried out the...
  12. A

    T test problem

    Dear all, Doing a t-test I got this results : 200 400 Mean 944.58333 960 Variance 402.08333 222.727273 Observations 12 12 Pooled Variance 312.4053 Hypothesized Mean...
  13. S

    Whether to use z test or t test

    hi team, I got the following question given below. According to me this should be solved using z test as the sample size is more than 30. But they are using t test. What is the correct method z test or t test? Please advice A social worker wants to know whether the mean annual salary of...
  14. 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...
  15. W

    Comparing habitat use across two different locations - mann whitney U?

    Hi, I'm really stuck with what test to use with my data. I have data on habitat use of 6 different habitat types across 2 locations and I'm unsure what test is most suitable. I thought initially mann whitney U but this doesn't seem to be working for me. I've attached the table below so you...
  16. L

    Likert scale data -can I use paired t-test? What about normality testing?

    Hey all! I have read many contradicting manuals and advice, so I decided to ask the best experts –you guys :) I have data from 40 subjects. I asked them to analyze eight short films (four sad ones, four neutral ones). I asked them to rate on a Likert scale 1 (not at all)-5 (very much) how much...
  17. T

    Comparing two groups and then the sub-groups (of the same)

    Hi I have four groups of variables A, B, C and D. The variables A and B also have (natural) sub-groups (say A1, A2, A3 and B1, B2 and B3). I want to compare them as follows: A - B - C - D (using ANOVA for 4 groups) A1 - B1 (using t test for two samples) A2 - B2 (using t test for two samples)...
  18. T

    Reporting t-test (table) + boxplot (mean, range and outliers)

    Hi I am looking for a reasonably appropriate way to report t-test along with a summary statistics. Initially I only wanted to go with box plots, and now I have to add t-test results as well. Is it a good idea to report the t-test in a table with a box plot for summary statistics as below image...
  19. H

    ANOVA maybe?

    I realized the answer but can't see how to delete.
  20. J

    2 sample independent sample t test

    Can someone please explain why you don't square the variance in this problem and do for others??