Make the broad-category map explicit
| Original label or suffix | Broad group |
|---|---|
| Food; Vegetables/Food; Dairy/Food; Packed/Food; Meat/Food; other /Food | Food |
| Apparel; Women/Apparel; Men/Apparel; Footwear/Apparel | Apparel |
| Toiletries; Cosmetics; Grooming | Toiletries |
| Utilities; Electronics; Accessories; Stationery | Utilities |
| Household | Household |
Use the same rule for every bill. Keep the original detailed label alongside the broad group so the aggregation is reversible by returning to source records. Do not silently move a category because it makes a particular pair of customers look closer.
For example, Bill 14’s Razor Blades, Razor and Shaving Lotion map from Grooming to Toiletries. Phone Charger, Earphones and Pencils map to Utilities. These six rows therefore contribute three Toiletries and three Utilities for Vignesh.
Try it yourself
Does Stationery stay separate in this five-column comparison?
Show explained answer
No. The lecture’s chosen grouping places it under Utilities.
Try it yourself
Does a broader map preserve every detailed product difference?
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No. It simplifies information. Keep the original rows for more detailed follow-up questions.
Try it yourself
Why must every customer use the same map?
Show explained answer
Otherwise the profile columns would have different meanings, so their distances would be inconsistent.