Why are there Blank or Null Values in Dropdown Filters?

Why are there Blank or Null Values in Dropdown Filters?

Why are there blank or null options in some dropdown filters like County or City?

Occasionally, you may notice blank or “null” entries in dropdown filters.  This happens when the underlying listing data is incomplete, inconsistent, or ambiguous.  In order to increase useability and promote a better overall user experience, we show the blanks where appropriate.

This can occur for several key reasons, especially in fields like County, City, or ZIP Code.


Don’t you clean the data before it appears in the dashboard?

Yes—we perform extensive data cleansing and normalization behind the scenes to correct, standardize, and improve listing data wherever possible. For example, the County field in the MLS often includes problematic values like "Other", "Out Of Area", or is simply left blank.  

When we detect these, we try to infer the correct value using State and Postal Code cross-referencing. If enough information is present, we’ll replace vague or unhelpful labels with a specific county name. However, if critical pieces (like ZIP Code or State) are missing or mismatched, we leave the field blank rather than introduce more errors.  In some cases, the MLS has asked us to do even more extensive data cleansing, like over-writing the County entirely with derived values.  All this is done in service of getting the most accurate statistic possible for a market; just because an agent entered the wrong County on the listing doesn't mean that listing didn't contribute to the economics of that area!


Could these blanks be due to errors in the MLS?

Yes—many blanks originate directly from the original MLS feed. If a listing is submitted with missing or incomplete values, our system receives it that way. When MLS systems update or correct listings later, those corrections will override our automated fixes in the next data refresh. We rely on accurate upstream data, and while we do everything we can to clean and enrich it, we won’t guess when too much information is missing.


Are blank filter values something I should be concerned about?

Not necessarily. They’re often limited to a small portion of listings.  That said, if you frequently see large numbers of blank values in a specific filter or area, it may be worth reaching out; we’re happy to investigate or notify the MLS.


Can I exclude blank values from my analysis?

Yes. In the filter dropdowns, you can deselect blank/null entries to focus your analysis on listings with complete data. However, be aware that this might exclude a handful of valid listings that simply haven’t had full metadata applied yet.

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