The note examines a generalization of a theorem of Bortkiewicz which relates the difference between a Paasche and a Laspeyres price index to a covariance between price and quantity relatives. The generalized theorem is used to demonstrate a number of interesting special applications. It turns...

The paper aims at indirectly estimating a time series of food prices from household expenditure data, focusing on foods considered as ‘junk’ relative to healthy foods. The “big 6” among the HFSS (high in fats, sugar and salt) foods identified by the Food Standard Agency have been...