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Some estimates of cross-price elasticity

The final part of this exciting trilogy is cross-price elasticity. (See here for estimates of own price and income elasticity.) Here we are looking for how demand for one product, say cars, is influenced by the price of another product, say petrol. The idea is to find a spread of examples from goods that are close substitutes (have cross price elasticity near 1) to strong complements (have an elasticity near -1). Within the literature there are a lot more examples of substitutes, like cars and public transport, than of complements, like cars and petrol. Indeed, it was a bit of a struggle to find any complements. Here are the examples I converged on: The book versus culture number is taken from the study by Ringstad and Loyland. The numbers for organic food are taken from the report by Bunte and co-authors on Dutch data. Those for alcohol are from a UK a study by Meng and co-authors. For numbers of public transport in the UK there is a  study by Paulley and co-
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Some estimates of income elasticity of demand

My previous blog looked at estimates of own price elasticity of demand. Now the focus moves on to estimates of income elasticity of demand. In a sense income elasticity should be easier to measure than price elasticity of demand because there is more variation in income than price. But I actually found it a lot harder to come by income elasticicities in the literature. And it was particularly difficult to get a nice spread of elasticities. Ideally we want some examples of luxury goods (with elasticity more than 1), normal goods (more than 0) and inferior goods (less than 0). The large majority of the examples I could find fitted in the 0.3-0.8 range. My rough interpretation of the literature is that 'simple' estimates tended to suggest things like eating out and health care were highly income elastic but more detailed work has lowered the numbers down. It was also the case that goods you might think of as luxuries where not. This could just be a self-selection issue. For i

Some estimates of price elasticity of demand

In the  textbook on Microeconomics and Behaviour with Bob Frank we have some tables giving examples of price, income and cross-price elasticities of demand. Given that most of the references are from the 70's I'm working on an update for the forthcoming 3rd edition. So, here is a brief overview of where the numbers come from for the table on price elasticity of demand. Suggestions for other good sources much appreciated. Before we get into the numbers - the disclaimer. Price elasticities are tricky things to tie down. Suppose you want the price elasticity of demand for cars. This elasticity is likely to be different for rich or poor people, people living in the city or the countryside, people in France or Germany etc.etc. You then have to think if you want the elasticity for buying a car or using a car (which includes petrol, insurance and so on). So, there is no such thing as the price elasticity of demand for cars. Moreover, the estimated price elasticity will depend o

Is it ever optimal to play a mixed strategy?

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