Independent Groups Pearson Correlation The Resear

Independent Groups Pearson Correlation The Resear

  • Discuss the three general purposes for using statistical tests in a quantitative study and identify one statistical test from each group.
  • Most
    important statistical tests
    Statistical test Description
    Fisher’s exact test Suitable for binary data in unpaired
    samples: The 2 × 2 table is used to compare treatment effects or the
    frequencies of side effects in two treatment groups
    Chi-square test Similar to Fisher’s exact test
    (albeit less precise). Can also compare more than two groups or more than two
    categories of the outcome variable. Preconditions: sample size ca. >60;
    expected number in each field 5
    McNemar test Preconditions similar to those for
    Fisher’s exact test, but for paired samples
    Student’s t-test Test for continuous data.
    Investigates whether the expected values for two groups are the same,
    assuming that the data are normally distributed. The test can be used for
    paired or unpaired groups
    Analysis of variance Test preconditions as for the
    unpaired t-test, for comparison of more than two groups. The methods of
    analysis of variance are also used to compare more than two paired groups
    Wilcoxon’s rank sum test
    (also known as the unpaired Wilcoxon rank sum test or the Mann–Whitney U
    test)
    Test for ordinal or continuous data.
    In contrast to Student’s t-test, does not require the data to be normally
    distributed. This test too can be used for paired or unpaired data
    Kruskal–Wallis test Test preconditions as for the
    unpaired Wilcoxon rank sum test for comparing more than two groups
    Friedman test Comparison of more than two paired
    samples, at least ordinal scaled data
    Log rank test Test of survival time analysis to
    compare two or more independent groups
    Pearson correlation test Tests whether two continuous normally
    distributed variables exhibit linear correlation
  • Explain what probability means.
  • What does p<.05 mean?
  • If the p =.15, what statement would you expect to see in the conclusion section of the research report with regard to the research and statistical hypotheses?
  • Briefly explain the value of using confidence intervals in study results. Support your answers with rationale from your text.