From LimeSurvey Manual
Revision as of 14:10, 3 June 2013 by Han (Created page with "Quota's")
A quota is used to set a limit on responses from defined groups of people on an active survey. Some common attributes used in defining quotas are things like gender, age, race, province/state. A quota can be added, edited or deleted by opening the quota window. Select the quota button on the Survey administration toolbar.
An english sample survey demonstrating the use of quotas at Limesurvey is available for download. You can import this survey at your Limesurvey system for testing ("import" tab at survey creation page): Limesurvey_sample_survey_Quotas.lss
Quotas are not automatically exclusive
Quotas are not comprehensive and automatically exclusive. To explain, let's imagine a survey that has a simple "Yes or No" question at the beginning.
You set a quota on this survey that contains a restriction of 20 users who have answered "Yes" to this question. The quota will be checked everytime somebody answers "Yes" to that question, and completes the whole survey. If the person answers the quota question but doesn't complete the survey, that answer-id is not going to be counted towards the quota. Once 20 people have done so, the quota action will be triggered by anyone else choosing "Yes".
However, if "No" is chosen, the quota system is never triggered. The survey will never restrict anyone who chooses no.
To set a limit on the number of "No" responses, you need to add an additional quota, restricting the number of participants who choose "No".
Supported question types
Currently only the following question types can have a quota defined for it:
- Multiple Choice
- Array - 5 Point Choice
- Array - 10 Point Choice
- Language Switch
- List (Radio)
- List (Dropdown)
- List with comments
Example of a quota
You might have to conduct a survey where you want to limit it to 25 male and 30 female respondents. You could then define a quota with a limit of 25 for the answer "Male" from your gender question in the survey. Another quota for the answer "Female" with a limit of 30 could be added as well. This will give you a maximum of 25 males who will be able to complete the survey, and a maximum of 30 females who can complete the survey.
A survey participant has to match all answers under the quota for it to apply to that response.
Adding a new Quota
Adding a new quota is really adding a framework for set of quota conditions. For a fully working quota you must firstly "Add a quota", and then "Add Answers" to that quota (see next section).
When adding a quota, you will be asked for a "Quota Name", the "Quota Limit", and a "Quota Action".
From version 1.85RC you will also have the option of setting your own unique quota "Quota Message", "url" and "URL Description" for each language used in your survey. You can also set "Autoload URL" so that the survey redirects users to the quota URL when the quota action is triggered.
All new quotas are assigned to the Survey you were viewing when you clicked "Set Survey Quotas".
- Quota Name: This is a name to reference the quota by, generally it should describe the quota it will represent.
- Quota Limit: This is maximum number of completed surveys to allow for the quota. This sets a limit that will be check when quota selected questions are answered during the survey.
- Quota Action: This is an action to perform when a participant is filling out a survey and lands up being part of a quota that has become full.
- Terminate Survey: This immediately terminates the survey, and closes the interview.
- Terminate Survey With Warning: This warns the participant and allows them to go back
- Autoload URL: This tells LimeSurvey to automatically redirect the participant to the URL when the quota action occurs. (Only In Version 1.85RC)
- Quota Message: The text displayed to your survey participant if the quota action is triggered (ie: the quota is full). (Only In Version 1.85RC)
- URL: The URL displayed to survey participants after the quota message, or the URL participants are automatically redirected to if 'Autoload URL' is turned on. You can use URL fields in this section. (Only in Version 1.85RC)
- URL Description: The text displayed for the URL. (Only in Version 1.85RC)
Once a quota is added, you will be able to add answers under the quota.
Adding an answer
- Select Question:
+When adding a answer under the quota, you will be shown a list of all available quota questions which are in your survey. If a question does not show up on the list, then its not yet supported with quotas. After you have chosen the question you want, press "Next" to move on to answer selection.
- Select Answer:
+Once selecting your question, you will be show a list of answers under that question. Here you will select an answer you would like to add to you quota, then press "Next".
Adding multiple quotas for the same question & subquestion
Adding multiple quotas for the same question is surely possible - but know that quotas are checked with a logical 'AND' operator - so to meet the quota the user has to answer both subquestion in that question like in your quota.
This means also that multiple quotas for the same subquestion or the same single choice question can never come true.
Quota and response data
All data is saved when the participant clicks the "Next" button. Even if the quota is full, the data submitted until the survey is terminated will be recorded. Nevertheless, such id is marked as "No Completed".
Quota and tokens
When tokens are used in a survey and the user is screened out due to a quota, then the according token entry is marked with the letter "Q" in the Completed column. That way the token is invalidated and the survey participant can't re-start the survey.