Interlocking quotas in Snap Online
In April's worksheet we described how to limit respondents to a Snap Online web survey by using quotas applied to categories of a single variable. This month we look at how to limit respondents in multiple categories, for example, by gender and age. This is known as an interlocking quota.
Step 1: Create a derived variable
To set up an interlocking quota, you first need to set up a derived variable in your survey.
- Click
to open the variables window. - Click
to add a new variable. Label the variable as Age and Gender. - Set the type to Derived and the Response to Single.
- Double click in the Label column, and add a code label of Men under 25
- Use the Tab key to move across to the Values column.
- Set the value to be the gender question equal to the male code, and the age question to the under-25 codes. In this case, that would be q1=1 and q2=(1,2)
- Tab again for the next label and set it to men over 25. Set the value to q1=1 and q2=(3,4,5).
- Repeat for women under 25 and over 25.
- Click the
button to save the variable.
Step 2: Set up the weight for the derived variable
- With the questionnaire open, click
to open the weights dialog. - Click to create a new weight
- Give the weight a name and label and then click in the value column for code 1. In this example, code 1 is males under 25.
- Type a value of 25 for code 2 and then use the tab key to move down to code 2. Continue adding quotas for your four groups.
- Click the button to save the weight.
Step 3: Set up the quota that associates the weight and the variable
- Select the Tailor | Quotas… option. The Quota Control dialog box appears.
- Click
. The Set Up Quota dialog box appears. - Change the quota name to GenderAge.
- Use
on the Variable and Weight options to make your selection. - Snap fills out the list to the right according to your settings.
- When you are satisfied that the quota has been set up correctly, click
.
Snap returns to the Quota Control window.Your quota is now listed in the Available Quotas pane.
Step 4: Activate the quota
- Ensure the 'Use Quota Control' tick box is selected in the Quota Control dialogue box and click to save the settings.