Metrics Average time spent on site

Hi RamyaSheela

You could check if there are outliers or high-variance days affecting the averages but also I recall this might be related to how Adobe Analytics calculates this metric at different levels. 

The metric "average time on site" is calculated by taking the timestamp differences between consecutive hits for a specific dimension item. Then AA sums these times and divides by the number of unbroken sequences ( continuous sessions without missing data points). When there's no subsequent hit to a dimension item (such as the final hit in a session), that last hit isn’t included in the calculation, which can lead to variations between totals and breakdowns. At least that is how I understand it and would make sense in this case here
(There is an example in the documentation:  https://experienceleague.adobe.com/en/docs/analytics/components/metrics/average-time-on-site )

The time calculation metrics can be quite tricky. I attempted to replicate what you're seeing, and I got essentially the same result. 

I decided to look at it both ways, breakdown the segment by the day, and then breakdown the day by the segment. In the top of the screenshot, I get a very short time on site for the segment, but then the day breakdown is much larger. In the bottom half, the day has a larger time spent on site, and then the breakdown gives the segment row a very small number again. 

What I think might be happening is that in the row with the segment, the time spent on site is looking at just the conditions that are in the segment (so only specific pages), which looking at a specific page or two is definitely going to be shorter than an entire visit. Then using the day breakdown I think is bringing in the whole visit again, not just the part in the segment.

I also looked at what happens with the date range. The date range for my panel is last week, so the header row of the second table below is the same time period as the date range for the first table. I had to block out visits, but they're the same in both tables. You can see that time spent per visit (seconds) is the same for both. 679 seconds divided by 60 gives 11.32 minutes, which is pretty close to what the bottom table has. So even with the date range it's doing something weird like it is with the segment. 

I'm not entirely sure what is causing it. I think @jennifer_dungan is going to try and figure this out too.

But I think my recommendation would be to put your segment either at the top of your panel (if you want it to apply to the whole panel) or above the metrics in your table (if you only want it for a particular table/column). Both of these solutions will result in no single line with a time against the segment itself, it'll result in having your dimension in the table and seeing the values associated with them. As for time periods, I would try and use panel date ranges instead of the component ones to avoid any miscalculations like this. If you do have to use the component date ranges, put them on top of your metric and use a dimension for the rows. I tested putting the segment and the date range on top of the metric and the totals are unaffected.

So to summarize - don't put the segment or date range directly against 'average time on site', use a dimension with the metric and apply the segments/date ranges you need above the metric or in the segment drop down at the top of the panel to avoid this issue.