Prime and total cost in relation to joint products. Cost of marketing. Insurance against risk. Cost of reproduction

Book 5, Chapter 7

Marshall, like many of his contemporaries, used long titles. 

§1. How should one price two goods that share common elements in their costs (e.g., a machine or management time) but are sold into different markets (e.g., passengers and freight on ships). Pricing from the cost side is tricky. Pricing from the demand side (“what the market will bear”) makes more sense, but it’s ultimately linked to costs, since competing firms selling similar goods and services must also cover their costs.

§2. A manufacturer will want to allocate marketing expenses among goods in proportion to their marketing “needs” but that manufacturer may cut that allocation in the most competitive markets (e.g., for loss leaders). Manufacturers who achieve economies of scale will have falling per unit costs but rising marketing costs based on trying to differentiate similar goods (e.g., cola advertising).

§3. Insuring against risk is often wise but allocating those costs can be difficult when they rise and fall with other actions. The price of fire insurance, for example, will fall if a building is built to reduce fire risks. Are those additional building costs part of construction or insurance?

§4. Marshall points out that risk aversion (the loss of bad outcomes outweighing the gains from good outcomes) is more prevalent than risk seeking behavior (p332):

It is true that an adventurous occupation, such as gold mining, has special attractions for some people: the deterrent force of risks of loss in it is less than the attractive force of changes of great gain, even when the value of the latter estimated on the actuarial principle is much less than that of the former… But in the large majority of cases the influence of risk is in the opposite direction; a railway stock that is certain to pay four per cent. will sell for a higher price than one which is equally likely to pay one or seven per cent. or any intermediate amount.

Kahnemann and Tyversky rediscovered these principles in the 1980s.

§5. In some cases, the cost of reproducing a good will be similar to its cost of production, with both closely tracking its price, but that relation weakens if production technologies or input prices have changed, and it breaks down if demand races ahead of supply (e.g., “quinine on a fever-stricken island”).

Marshall ends the chapter with the advice that non-economic readers skip the next seven chapters (!), but I won’t. Fasten your seatbelts!


This post is part of a series in the Marshall 2020 Project, i.e., an excuse for me to read Alfred Marshall’s Principles of Economics (1890 first edition/1920 eighth edition), which dominated economic thinking until Van Neumann and Morgenstern’s Theory of Games and Economic Behaviour (1944) and Samuelson’s Foundations of Economic Analysis (1946) pivoted economics away from institutional induction and towards mathematical deduction.

Author: David Zetland

I'm a political-economist from California who now lives in Amsterdam.

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