Nowcado Search Algorithm

For those interested, we thought we’d explain a subtle change in Nowcado’s (get it for Android or iOS) search results coming in the next update, in case you notice the behavior is somewhat different and were wondering why.

We have noticed and heard some feedback that the current Nowcado search results are too strict and unforgiving of small spelling errors, especially involving whitespace and partial words. This is because each word in the search bar was only allowed about 1-2 characters flexibility.

Instead, we will now be using ngrams. It works by scoring each product based on the degree to which the letter sequences in your search bar match the letter sequences in each product’s name and category. For example, searching for “whiskey” will now match against “whiskey”, “whi”, “whis”, “whisk”, “his”, “hisk”, etc. The more matches there are, the higher the relevancy score. The ordering of the search results will be influenced by each product’s relevancy score, price, and distance (weighted depending on which sort you specify).

This could mean that you see a few products that aren’t very relevant (i.e. “pineapple” flavors match “wine”), but only near the bottom of the search results. We feel this is much more preferable than giving zero results for a minor misspelling of a brand. This change also allows us to easily tweak the scoring of results in the future, based on common patterns that we see that seem less than intuitive.

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One thought on “Nowcado Search Algorithm

  1. […] This one was a bit of “Spring cleaning” on our side (it is Spring now, right?) that reorganizes some of the database to streamline server calls and improve app performance. The only noticeable change for you, besides being faster, is that we have redone our searching algorithm to be much more forgiving of spelling errors and partial words. You may see more results, or in a slightly different order, for certain searches. (See details in our post from yesterday.) […]

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