[gruez]

Sampling bias is going to be a real issue because there's going to be a strong incentive for people who think inflation is high, or is actively experiencing high inflation to participate. Also, if you're only tracking your expenses and not using a fixed basket, the index will end up including lifestyle inflation as well.

[jxramos]

that's an excellent point. Clarify a bit the notion of the fixed basket, I'm thinking mostly of unit prices. I think that could get a bit fuzzy too because of practices like shrinkflation cluttering up the analysis. I think SKUs should actually be tied to fixed things like weight where applicable. I wonder what the rules are surrounding that, basically make it so that if you change the weight of a product you have to issue a new SKU. Might be a messy figure overall but still capable of shedding some insight people would be interested in I'd think.

[gruez]

By "fixed basket" I'm talking about the issue of people getting higher quality goods as their income increase, or buying more or less of something (eg. takeout) as their lifestyle changes.

[jxramos]

yah those instances I would think would break a given "SKU run" if you will, it would have its run in an individual's life under a given time regime. It would phase in and it would phase out.

[jxramos]

I had to lookup some of these points on SKUs, this is good background https://www.shopify.com/retail/what-is-a-sku-number