Cluster 500 keywords by shared URLs, not by words

Cluster 500 keywords by shared URLs, not by words
String-matching groups synonyms that rank on different pages. SERP-overlap clustering is the fix. From a 500-keyword seed we built 41 clean clusters this way.

— Step 1: pull top 10 results for every keyword
— Step 2: two keywords share a cluster if they share 3+ of the same ranking URLs
— Step 3: set the threshold ▇▇▇ 3 URLs = tight, ▇▇ 2 = loose
— Step 4: name each cluster by its highest-volume member
— Step 5: assign one URL per cluster, never two

At a 3-URL threshold we got 41 clusters; at 2-URL it collapsed to 26 (over-merged). The so what: word similarity grouped 18% of terms wrong that SERP overlap caught.

Benchmark of the week: 3 shared URLs is the standard cut line for tight topical clusters.