A characteristic of tastes or technology that a combination of commodities is preferable to any one on its own. If someone prefers a slice of bread and half a gram of butter to either a whole slice of bread or a whole gram of butter, they have convex preferences. If it is easier to make one car using ten men and ten machines than to make it using twenty men and no machines or using twenty machines and no men, the production technology is convex.
Convexity implies that combinations of products are more desirable than extremes.
It is itself usually implied by diminishing marginal utility . It takes its name from the shape of the indifference curves or isoquants that convexity generates. The Penguin Dictionary of Economics 5. All rights reserved.