Explore variable
From the Analysis menu choose Explore variable, and choose the variable(s) you want to analyze, then hit OK.
- Optionally, uncheck the Frequencies, if you want to skip that analysis.
- Optionally, change the central tendency value, if your hypothesis is a different value.
The following values and graphs will be displayed (see also the common elements of the results):
Raw data
| Results | For interval data | For ordinal data | For nominal data |
|---|---|---|---|
| Sample size | Number of observed and missing cases | Number of observed and missing cases | Number of observed and missing cases |
| Raw data | Dot plot | Dot plot of the order of the values | Histogram |
Sample properties
| Results | For interval data | For ordinal data | For nominal data |
|---|---|---|---|
| Frequencies | Table of all values in the variable with the following details: * Value * Frequency * Relative frequency (percentage of that value of all cases) * Cumulative frequency * Cumulative relative frequency |
Table of all values in the variable with the following details: * Value * Frequency * Relative frequency (percentage of that value of all cases) * Cumulative frequency * Cumulative relative frequency |
Table of all values in the variable with the following details: * Value * Frequency * Relative frequency (percentage of that value of all cases) |
| Descriptive statistics | Mean Standard deviation Skewness Kurtosis Range Maximum Upper quartile Median Lower quartile Minimum |
Maximum Upper quartile Median Lower quartile Minimum |
Variation ratio |
| Graphs of the data | Combined graph of histogram, individual data on x axes and box plot | Combined graph of histogram, individual data on x axes and box plot of the order of the values |
Population properties
| Results | For interval data | For ordinal data | For nominal data |
|---|---|---|---|
| Normality | * Shapiro-Wilk test * Histogram with normal distribution (normal distribution has the same average and standard deviation as the data) * Q-Q plot |
(Only for interval variables) | (Only for interval variables) |
| Parameter estimation | * Mean and its confidence interval * Standard deviation and its confidence interval |
Median and its confidence interval | Confidence interval of the relative frequencies (multinomial proportions with Goodman method) |
| Graphs of the population parameters | Graph with mean and confidence interval or median for non-normal variable | Graph with median | |
| Hypothesis test and sensitivity power analyses | If the data are normal (measured with Shapiro-Wilk test), then one-sample t-test and (new in v2.3) Bayesian one-sample t-test, otherwise Wilcoxon signed-rank test (see CogStat specific details) For one-sample t-test sensitivity power analyses |
Wilcoxon signed-rank test (see CogStat specific details) |