What is the purpose of the setAudienceManagerFields and setAnalyticsFields scripts?

The following two scripts are being automatically generated and depending on the browser, is causing some small layout issues:

<script type="text/javascript" async="async" src="........._setAudienceManagerFields”>
<script type="text/javascript" async="async" src="...........setAnalyticsFields">.

I am not able to find any documentation on the scripts. What is the purpose of them?