Do I rely on instances or occurrences for unspecified?

[#1]

I've implemented a new eVar which captures zip code on confirmation page. Since it has been implemented, occurrences of unspecified has jumped. Now my question is, is it accurate or does it persist through the pages to the confirmation page (unspecified)? Do I rely on instances or occurrences for this case? Could not reproduce an "unspecified" value for the newly created eVar i had done.

[edwardb44196902 · Accepted solution]

Occurrences include persisted values too, and "Unspecified" will never have an Instance.

[edwardb44196902 · Accepted solution]

thank you, so when going off data and i see unspecified for a certain eVar, does that mean something is not implemented correctly? how can I compare data to make sure it's coming in correctly? thanks

[ShamshulA]

Typicall evars are set to persist although that can be changed to not persist....

Instances: Shows the number of times a given variable was defined in any image request, including PageView and Non-PageView Server Calls.

Occurrences: Counts the number times a variable was defined or persisted across both PageView and Non-PageView Server Calls.

[ShamshulA]

@edwardb44196902 To understand why there is an unspecified line item while checking the Analytics report with Occurrences metric, we need to understand the following definitions and scenarios.

Occurrences higher than Instances: This outcome is expected for conversion variables, as occurrences also includes the number of times the variable was defined (instances).

Instances higher than Occurrences: This outcome is not possible in reporting, as all instances are recorded as occurrences as well.

Occurrences vs. Instances : Occurrences count hits where a dimension item was set or persisted. Instances do not include hits where a dimension item persists.

Occurrences vs. Page views : Occurrences include all hit types, including page view tracking calls ( t() ) and link tracking calls ( tl() ).

The page views metric only includes page view tracking calls, and excludes link tracking calls. eVar and prop reports include both. To overcome this it is recommended to use instances as metric for (eVar) while checking eVar report.