In this article, the author considers the effect of brand names on dem
and by examining the price ratios of used twin automobiles. Twins usua
lly are made in the same plant and have essentially the same physical
attributes but different brand names. If the models of a twin pair are
perceived as perfect substitutes, their relative price should equal u
nity. Brand names could cause the demand for twin models to differ if
consumers use the brand names to make inferences about unobservable qu
ality. Consumers also might prefer one brand to another for prestige o
r status. The relative prices of most of the twin pairs in the sample
differ from unity, which implies that consumers do not perceive the tw
in models to be perfect substitutes. Parent-brand quality and other br
and factors are related to the relative prices of the twin pairs. The
results suggest that consumers rely on information about the parent br
and to make inferences about individual products that carry the parent
name. The results have implications for firms' branding policies.