Matrix coding query
Matrix Coding queries enable you to see coding intersections between two lists of items.
You can use Matrix Coding queries to ask a wide range of questions about patterns in your coded data and gain access to the content that shows those patterns.
For example—depending on how you coded your data, you could compare Positive and Negative attitudes towards different themes:
Or compare what different cases have said about an issue:
You could also explore how terms are used in different contexts. For example, what do people say about Habitat in relation to the Economy?
Refer to Move forward with queries and visualizations for more ideas about how you can use Matrix Coding queries to explore your data.
The resulting node matrix can be saved in your project as a query result or with your nodes in the Node Matrices folder.
When you are working with a node matrix, you can:
- Open a node from a matrix cell to see all the content coded at the cell (at both the row and column nodes)—double-click on a cell to open the node.
- Apply shading to cells to make it easier to see patterns in the matrix
- Change the information displayed in the matrix cells—for example number of files coded or number of nodes coded
- Filter or sort the matrix
- Transpose the columns and rows
If you want to view the matrix as a chart, click the Chart tab. You can make changes to the chart type, title, labels, gridlines, and rotation.
Create a matrix coding query
If you are not familiar with NVivo queries, you may want to create your query using the Wizard—the Wizard guides you through the process of setting your query criteria. However, not all query features are available in the Wizard, so you may sometimes want to create your query outside the Wizard.
On the Explore tab, in the Query group, click Query Wizard.
The Query Wizard opens. Follow the steps on the Wizard.
Choose the query you want to run.
Click Find coding intersections between two lists of items.
Define the rows and columns for your matrix.
Click Add Selected Items to add a row/column that represents a specific node, file, case or other project item. For example, you could add a row/column that represents a thematic node or content coded to case nodes with the attribute value female.
Click Add Attribute Condition to add a row/column that represents all the files or cases that meet specific attribute value criteria. For example, you could add a row/column that represents all cases where the attribute value for age is greater than 40.
Choose where you want to search.
Choose whether you want to search text in all your files, or restrict the search to selected items or folders.
Choose whether to add the query to your project.
You can run the query once or choose to add it to your project (and run it).
If you choose to add it to your project, you must enter a name. You can optionally enter a description.
- Click Run.
On the Explore tab, in the Query group, click Matrix Coding.
1To limit the scope of the query, choose Selected Items or Selected Folders. For example, you could search only the files in your Interviews folder.
2When looking for coding co-occurrence (where content is coded at the intersection of two nodes) you would typically use the AND search operator. However, you could choose a different search operator for the lists of items. For example, search for content coded at Tourism where it is NEAR content coded at Water Quality. You can also show or hide the hierarchical name of an item to simplify the query results.
3Add items to the Rows panel, drag and drop them from List View or click the plus sign.
4Add items to the Columns panel, drag and drop them from List View or click the plus sign.
5Click an icon on the bottom right of the Rows or Columns panel to:
- Specify how sets or search folders should be handled. For example—query a whole set, or split the set into separate items.
- Query the coding done by a selected users. For example, include only your coding in the scope of the query.
- Reorder selected items in the list.
6Click Run Query. You can click the arrow to automatically save the results or you can click Save Results after running the query.
- To save the query, click the Add to Project button and enter the name and description (optional).
- If you include an 'aggregate' node in the scope of a query, content coded at the node and all its direct children will be included in the query results.
When the query has finished running, the results are displayed as a temporary preview in Detail View.
Save the preview results as a node matrix
You can save the preview results as a node matrix in your project—either in the Results folder or Node Matrices folder. This is useful when you want to keep a record of the coding in your project at a particular point in time.
- Click on the query results in Detail View.
- On the Matrix tab, in the Query group, click Store Query Results.
- Enter a name and description.
- Click OK.
- By default new node matrices are created in the Results folder, unless you choose another location.
- You can choose to save the results in your project before you run the query—by setting your preferences on the Query Options tab in the Matrix Coding Query dialog box.