Mmmm Burgernomics

Free exchange, the Econmist's blog has posted a note, Weighting Game, that says Big Mac burger patties vary in size by country. This could have an impact on the Big Mac index. Should the economist decide to re-weight the index for patty weight, I suggest they balance their new weighting with an understanding that patties are only a portion of the total cost of input into a Big Mac. It would be easy to overweight the weight of the patty weight in the new index.