Where a specified sample of web survey respondents is required, quotas may be used to limit the number of respondents in identified categories. For example, to limit the numbers of males and females, or to limit the numbers in each age group.
Quotas can only be applied to Web: Snap WebHost surveys. They may not be used with Web: HTML or Web: Framed HTML surveys.
Once the quota has been reached, further respondents will be routed to the end of the questionnaire. It is therefore helpful if questions used by the quota are placed as near the beginning of the survey as possible to avoid other, unnecessary questions being asked.
In this example we introduce a quota that restricts the survey to the first 50 males and 50 females.
The first step is to create a weight matrix to record the quota targets.
1. With the questionnaire open, click the Weights icon to bring up the weights dialog box. Click to create a new weight.
2. Give the weight a name and label and then click in the value column for code 1. In this example, code 1 is male and code 2 is female. Type a value of 50 for code 1 and then use the tab key to move down to code 2. The value will again be 50. Click the button to save the weight.
The next step is to set up the quota itself which will associates the previously built weight with the quota question.
1. From the main toolbar, select Tailor and then Quotas… from the drop-down menu.
2. Click to create a new quota.
3. Give the quota a name and from the variable drop-down, select the question for which you wish to apply the quota to. Use the weights drop-down to select the weight set up previously. Once both are selected, the table will reflect the quota details to confirm that no more than 50 male and 50 females may complete the survey.
Each quota contains a text box for a message. By default, this message will be shown to respondents who exceed the quota (see the closing notes below).
4. Click to save the quota.
Ensure the ‘Use Quota Control’ tick box is selected in the Quota Control dialogue box and click to save the settings.
The survey is then ready for publishing to Snap WebHost.
During interviews the quota will be automatically monitored. As soon as a respondent leaves the page with the quota question on, the counts to date will be compared with the quotas to see if they should continue with the remainder of the questionnaire or not.
Those outside of the quota (the 51st or subsequent male and the 51st or subsequent female) will be routed out of the questionnaire to the page quotafull.html. You can load your own version of this file as part of your survey on Snap WebHost. If you don't load your own version the your quota message will be presented to the respondent on the default page.