What is the maximum number of invitations which can be sent out for large deployments or when using an External Sample?

Alida has been getting a number of requests from customers wanting guidance on what is the maximum size of a community which the system can handle in terms of its members, the number of email invites which can be sent, and the number of survey completes. We know from historical numbers how many emails can be delivered in a given hour and the maximum community size the platform can support. The area that is more variable is the maximum number of completes; this is dependent on deployment size, response rate, length of the survey, and the complexity of the survey.

In order to calculate the maximum deployment size that can be sent out, the following basic formula can be used:

MaxDeploymentSize (per hour)  =  MaxSurveyStartsVisual(2200)/(MacConncurrentResponseRate * ExpectedResponseRate)  

For example, assuming the survey does not have visual questions and the expected response rate is 40% you would get the following:
 

MaxDeploymentSize (per hour) =  2200/(0.1 * 0.4)

Or

MaxDeploymentSize (per hour) = 55000  
 

This result matches what has been seen with the market panels run and managed by Alida.
The suggested calculation for invitation deployments applies to Sparq 1 and Community.

Details

Performance Testing Summary

The main goal for performance testing was to determine how many people can respond to a survey at a given time before the respondents experience unacceptable performance levels from the platform. 

From these results customers can then determine the maximum deployment size to send out their survey.

Inputs

AverageResponseRate = Average response rate for a survey

This is the main input to determine the Deployment Size. You can make use of a soft launch of your study to assist in determining this. Soft Launches also allow you to identify issues and errors prior which can then be resolved prior to a full launch.

Constants as a result of historical analysis

MaxConcurrentResponseRate = 10%

Through our analysis of our largest communities with the highest response rates we have determined that 10% of respondents in a given deployment respond within the busiest 10 minute period.

Constants as a result of performance test results

MaxSurveyStartsVisual = 2200

After our performance testing, this is the maximum survey starts within a 10 Minute period for survey before respondents would not be able to respond with an acceptable level of performance from the system.
 
Outputs

MaxDeploymentSize (per hour) = Deployment size that can be sent to invite members to respond to a survey per hour. 
 

Conclusion

With the above formula you are able to determine the maximum number of invitations you can deploy per hour. Please be aware that it is always recommended you perform a Soft Launch when sending out a study.
 

More Information

Please click on the following links below for more information:

• Survey statistics
• Recipient size limits and soft launches