A COMPARISON OF AUTOMOBILE DEMAND EQUATIONS

摘要: This paper reports the testing of hypotheses concerning: (i) whether household is better viewed as planning over a single-period versus multiperiod horizon; (ii) in single-asset or multiasset framework; (iii) relative importance substitution and wealth effects sources change stock demand for automobiles. The findings are that multiperiod, model best describes demand, separation theorem which implies zero effect rejected, seven times more important than effects. THE ECONOMIC LITERATURE CONTAINS several empirical studies automobile [3, 7, 8, 10] theoretical models [1, 4, 5, 6, 14] could be applied to demand. Two aspects theory not fully reflected implications horizon possibility among assets. Theoretical [5 15] assume imply relevant asset prices user costs appropriate constraint wealth. In contrast, most use purchase rather costs, income addition, [4 5] permit variety goods, whereas restrict substitutions automobiles consumption goods. To extent estimated equations misspecified, prevailing conclusion may due left-out-variable bias. investigates each these three issues-the length horizon, range substitutions, effects-by estimating same set data alternative reflect different assumptions about substitutions. Initially, consumption-saving decision stated used derive arguments broadest equation. A linear approximation this equation using quarterly United States covering years 1952-1972. Then estimate compared competing derived under restrictions on model. Specifically, single-asset, single-period, versions restricted have appeared literature compared. are: estimates quite sensitive specification bias, dominant