Contents
What kind of statistical analysis should I use?
Using the hsb2 data file, let’s see if there is a relationship between the type of school attended ( schtyp) and students’ gender ( female ). Remember that the chi-square test assumes the expected value of each cell is five or higher. This assumption is easily met in the examples below.
How to choose the right type of statistical test?
Nominal: represent group names (e.g. brands or species names). Binary: represent data with a yes/no or 1/0 outcome (e.g. win or lose). Choose the test that fits the types of predictor and outcome variables you have collected (if you are doing an experiment, these are the independent and dependent variables ).
When to use independent samples in statistical analysis?
An independent samples t-test is used when you want to compare the means of a normally distributed interval dependent variable for two independent groups. For example, using the hsb2 data file, say we wish to test whether the mean for write is the same for males and females. t-test groups = female (0 1) /variables = write.
When to use a non parametric statistical test?
If distribution of the data is not normal or if one is not sure about the distribution, it is safer to use non-parametric tests. When comparing more than two sets of numerical data, a multiple group comparison test such as one-way analysis of variance (ANOVA) or Kruskal-Wallis test should be used first.
Using the hsb2 data file, let’s see if there is a relationship between the type of school attended ( schtyp) and students’ gender ( female ). Remember that the chi-square test assumes that the expected value for each cell is five or higher. This assumption is easily met in the examples below.
How is experimental data used in statistical analysis?
Experimentation often generates multiple measurements of the same thing, i.e. replicate measurements, and these measurements are subject to error. Statistical analysis can be used to summarize those observations by estimating the average, which provides an estimate of the true mean.
When to use Fisher’s exact test for statistical analysis?
Again we find that there is no statistically significant relationship between the variables (chi-square with two degrees of freedom = 4.577, p = 0.101). The Fisher’s exact test is used when you want to conduct a chi-square test but one or more of your cells has an expected frequency of five or less.