Purpose
This App can be used to perform Chi-Square Test for contingency table to determine whether there is significant evidence of association between two variables.
Installation
Download the file "Chi-Square Test for Contingency Table.opx", and then drag-and-drop onto the Origin workspace. An icon will appear in the Apps gallery window.
Operation
- Activate a worksheet with data and click the icon in the Apps Gallery window to open the dialog.
- Select a column for Group Label and multiple columns for Data Range.
- The column category can be stored in different column label rows (Long Name, Comment, Paramter etc.).Choose one for Column Category.
- Click OK button.
Sample OPJU File
This app provides a sample OPJU file. Right click the App icon in the Apps Gallery window, and choose Show Samples Folder from the short-cut menu. A folder will open. Drag-and-drop the project file Chi-Square Test for Contingency Table Sample.opju from the folder onto Origin. The Notes window in the project shows detailed steps.
Note: If you wish to save the OPJU after changing, it is recommended that you save to a different folder location (e.g. User Files Folder).
Algorithm
The Pearson Chi-Square test statistic: \(Q_p=\sum_{i}^{}\sum_{j}^{}(n_{ij}-e_{ij})^2/e_{ij}\)
The Likelihood Ratio Chi-Square test statistic: \(G^2=2\sum_{i}^{}\sum_{j}^{}n_{ij}ln(n_{ij}/e_{ij})\)
where \(n_{ij}\) is the observed frequency in table cell (i, j) and \(e_{ij}\) is the expected frequency for table cell (i, j).
Expected frequency: \(e_{ij}=(n_{i\cdot}n_{\cdot j})/n\)