Why did my sentiment score drop in Chattermill?
The Chattermill help pages give 4 common reasons. The first to rule out: Net sentiment is the share of positive mentions minus the share of negative ones, so it can fall when negative mentions rise even if positive mentions hold steady.
What causes it?
Net sentiment is the share of positive mentions minus the share of negative ones, so it can fall when negative mentions rise even if positive mentions hold steady.
In the Chattermill help:
This is our own metric, calculated by subtracting % of Negative theme mentions from % of Positive ones.
Common terms and definitions | Chattermill User Guides, read 2026-11-12.The index is worked out only on the responses your filters select, so a different filter can give a different number.
In the Chattermill help:
Measures the number of negative theme mentions within a set of responses based on your filter selection
Common terms and definitions | Chattermill User Guides, read 2026-11-12.One response can carry several theme mentions, so the index can pass 100, unlike a percentage.
In the Chattermill help:
Unlike a percentage, this number can be more than 100 because one response could have many theme mentions.
How we calculate Positivity & Negativity Index | Chattermill User Guides, read 2026-11-12.The index divides mentions by all responses, so a change in how many responses came in can move it even when mentions stay the same.
In the Chattermill help:
This is then divided by the total number of responses (for all categories), and multiplied by 100.
How we calculate Positivity & Negativity Index | Chattermill User Guides, read 2026-11-12.
How do I check it myself?
Filter feedback to one theme at a time to see which theme moved the score.
In the Chattermill help:
Click on any theme to filter your results.
The New Feedback Page | Chattermill User Guides, read 2026-11-12.Use the same saved filters each time you compare, so a change in filters is not mistaken for a change in feedback.
In the Chattermill help:
To apply a set of filters you've previously saved, click Default filters in the top left and choose a segment.
The New Feedback Page | Chattermill User Guides, read 2026-11-12.
How does Chattermill work with Feder?
- Connect Chattermill to Feder and it joins your Experience apps.
- When you connect Chattermill, Feder checks the connection straight away and shows Connected only when that check passes. If a reading cannot be taken later, Feder shows it as not read, never as zero.
Some numbers are too quiet to judge daily, such as a form filled in a few times a week. Until there is enough of your own history to judge a change, Feder says it is still learning and scores nothing, rather than guessing.
See whether you can trust the numbers in Chattermill, one of your Experience apps. Feder only reads. It never changes anything in Chattermill.
What else goes wrong with these numbers?
- Why did the number of responses in Chattermill drop?Chattermill
- Why did my Chattermill NPS or CSAT numbers change after a data upload?Chattermill
- Why did Google Analytics stop collecting data?Google Analytics
- Why aren't my key events showing in Google Analytics?Google Analytics
- Why does Google Analytics show (not set)?Google Analytics
See every question.
Where do these answers come from?
Every cause and check on this page comes from the Chattermill help pages, quoted above with the date we read them. Last reviewed 2026-11-12. We read them again by 2027-11-12. If one changes, this page changes or comes down.