ttest

  1. C

    T test vs. Chi Sq

    Is an unpaired t-test the same as a chi sq test with respect to the resulting p-value if I'm using categorical data (0s and 1s)? Thanks.
  2. M

    Correct statistical test to compare pre and post questions (dummy variable)

    Hi friends, What is the correct statistical test to compare a group who was tested in two points in time (pre and post) The same people. I have a dummy question that was asked in pre and post test (exact the same question): 1=correct to the questions 0=incorrect I want to see if there...
  3. A

    Performing a t-test on averages??

    Is it "statistically legal" to perform a t-test on the averages of two groups? In other words, the data set values are averages themselves (example: a ttest performed on GPAs). I realize that doing a ttest on averages is pretty much like taking the average of averages, which is in most cases a...
  4. R

    Independent sample t test!

    Hi all! One basic question I hope you can answer. I would really appreciate it :D:D I have to columns of data. Both are daily returns (scale variable). The second column does not containt as many observations as column 1. e.g column 1 column 2 0,2%...
  5. W

    Spss Paired sample T test Eyes Doctor

    Hello.I have to do research using spss. I need urgent help the instructor told me to do on spss v 10 while i have v 17 is it ok to do so 2nd thing that this research is regarding eye patients sample size is 44 but eyes of patients are 88 so how to enter data for 88 eyes...i have to consider...
  6. L

    Need help to test the significance

    I want to make a test to see if the difference is significant or not. What I have is two different groups of values (one with 31 values and the other with 28 values). These values have nothing to do with each other, (since it is values of iron intake for people in two different cities). I need...
  7. J

    Paired or Independent?

    Dear all, For my thesis I have created 2 portfolios of 250 stocks each (randomly selected). I hypothetically buy them on the 1st of January and sell them back on the last trading day of the year. I have calculated the returns over the year and collected them in 2 groups of 250 each...