Sub population (AskiaAnalyse)

A sub-population allows you to present tables and charts based on a sub-set of the individuals in your survey, such as people in a particular subgroup (e.g. females) or a logical combination of groups (e.g. credit card users aged 35-44 and living in Canada). Sub-populations can be applied to your tables and charts in the general tab of table definition.

A sub-population provides one way to apply a "filter" to the data you wish to present, based upon the answers given by individuals to the questions in your survey.  Filtering can also be applied by changing the universe on the table or chart. The universe also allows you to vary the base for your table, and offers a pre-defined set of eligibility criteria to select from (e.g. all answering).  You may also apply any existing sub-population as your universe selection, which effectively allows you to filter your table by two sub-populations at the same time. Respondents must meet both criteria to be included (i.e. they are logically and-ed). 

A universe can also be used to apply a sub-population, so that you can have two sub-population filters applied to the table.  If doing so, it must first be created using one of the sub-population creation methods described on this page. 

Unless you explicitly apply a different sub-population, Askia will set the sub-population to show All interviews in any table or chart you create.

In this topic:

• Applying an existing sub-population to a table definition
• Defining or amending a sub-population using the full dialog
• Creating a new sub-population
• Quick mode: creating a subpopulation for each response 

Applying an existing sub-population to a table definition

To apply an existing sub-population to a table definition:

1. When defining a table, open the general tab.
2. In the sub-population list, select the sub-population you want to apply (if only all interviews is present, then you have no sub-populations currently defined: click ► to begin defining a sub-population).

Defining or amending a new sub-population using the full dialog

The full dialog allows you to define sub-populations using logical combinations to any level of complexity, as well as allowing you to amend or delete existing sub-population definitions. Each of the following allows you to call up the sub-population dialog:

• From the tools menu, select sub population.

• When defining a table, from the general tab click the extended menu icon ► next to the sub-population list.

• When defining a table, from the general tab click the extended menu icon ► next to the universe list.

The context (right-click) menu gives you access to the following features:

OPTION	DESCRIPTION
New	Add the selected response(s) to the result table's rows.
Copy	Create a copy of the selected sub-population. The logical definition will be copied into a new sub-population. You will need to enter a new name for the sub-population.
Save	Save the sub-population currently being defined or modified.
Delete	Delete the currently selected sub-population.
Delete multiple	This will present a check-box list showing all currently defined sub-populations from which more than one sub-population can be selected for deletion. Select all any items to delete and click the delete button at the bottom of the window. You will be asked to confirm your choice before the selected items are deleted.

When defining a new sub-population, complete or select details for the sub-population as follows:

Creating a new sub-population

Choosing the mode to define your condition

By default, the definition mode selected will be GUI. This mode allows you to define simple conditions by drag-and-drop or by clicking on the desired options from a pop-up list. 

GUI mode allows you to combine up to four conditions.

To define a condition in GUI mode:

1. Click ... next to a condition's box to define that condition. The directory tree for your questionnaire appears.

2. Select the question, then the item (or items) to which your condition applies.

3. Click  to save your condition.

4. Click OK to close the sub-population window.

You can also simply drag and drop questions or responses from the left-hand pane into the sub-population list in GIUI mode.

In advanced mode, you can combine as many conditions as you want by using AskiaScript.

To define a condition in advanced mode:

1. Drag the questions or items to which you will apply a condition into the condition window or write script to define your condition.

2. Click  to save your condition.

3. Click OK to close the sub-population window.

See also:

• Defining a sub-population in the GUI
• Defining a subpopulation with script

Quick mode: creating a subpopulation for each response

You may also create a sub-population based on individual responses of an existing variable by using the context menu option Create a sub-population for each response which is available by right-clicking in either the questionnaire panel or the response distribution panel. Right click on the question in the questionnaire panel to build sub-populations for every response option to the question, or alternatively, right click on one or more response options to create sub-populations selectively. 

To define one sub-population for each response option to a question:

1. Right click on the question 
2. From the context menu, select Create a sub-population for each response.

To define sub-populations selectively:

1. Click on a question in the questionnaire pane to select it.
2. Click on the first response you wish to select in the response distribution panel, located below the questionnaire tree.
3. Optionally, select additional response options by using CRTL+click and/or SHIFT+click to select a consecutive block of response options within the response distribution panel.
4. When your selection is complete, right click on any of the selected response options and select Create a sub-population for each response from the context menu.