Suggest reasonable missing value annotations

[alyssadai]

Is there an existing issue for this?

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New feature

When annotating missing values for a column with many unique values, currently it is quite tedious (and error-prone, as you can easily miss values) to scroll through all possible values to find the one you are looking for. This is especially challenging when the missing value is an empty string "", as you cannot easily CTRL+F it on the page.

It would be helpful if at this step the annotation tool could check the column for some values reasonably expected to represent missing data, e.g., ["NA", "na", "n/a", "", "null"] and suggest them as missing values for the user to annotate. Ideally, any detect possible missing values would be grouped together in a section at the top of the table of unique values, so they are easy to spot and annotate right away.

Unclear documentation

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