06 Consumer Behavior Copyright © 2012 by The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill/Irwin

Law of Diminishing Marginal Utility Utility is the satisfaction one gets from consuming a good or service Not the same as usefulness Subjective Difficult to quantify LO1 6-2

Law of Diminishing Marginal Utility Util is one unit of satisfaction or pleasure Total utility is the total amount of satisfaction Marginal utility is the extra satisfaction from an additional unit of the good MU = ΔTU/ΔQ LO1 6-3

Law of Diminishing Marginal Utility As consumption of a good or service increases, the marginal utility obtained from each additional unit of the good or service decreases Explains downward sloping demand LO1 6-4

Total Utility and Marginal Utility 10 20 30 8 6 4 2 -2 1 3 5 7 Total Utility (Utils) Marginal Utility (Utils) (1) Tacos Consumed Per Meal (2) Total Utility, Utils (3) Marginal Utility, Utils TU 1 2 3 4 5 6 7 10 18 24 28 30 ] 10 8 6 4 2 -2 MU LO1 6-5

Theory of Consumer Behavior Rational behavior Preferences Budget constraint Prices LO2 6-6

Utility Maximizing Rule Consumer allocates his or her income so that the last dollar spent on each product yields the same amount of extra (marginal) utility Algebraically MU of product A MU of product B Price of A Price of B = LO2 6-7

Deriving the Demand Curve Price of Orange $1 $2 4 6 Quantity Demanded of Oranges Quantity Demanded Price Per Orange $2 4 1 6 DO LO3 6-8

Income and Substitution Effects Income effect The impact that a price change has on a consumer’s real income Substitution effect The impact that a change in a product’s price has on its relative expensiveness LO4 6-9

How people actually deal with life’s ups and downs Prospect Theory How people actually deal with life’s ups and downs People judge things relative to the status quo People experience: Diminishing marginal utility for gains Diminishing marginal disutility for losses People are loss adverse LO5 6-10

Losses and Shrinking Packages Consumers see any price increase as a loss relative to the status quo Producers are reducing package size instead of raising prices LO5 6-11

Framing Effects and Advertising Consumers evaluate events in a particular mental frame New information alters the frame in which the consumer defines whether situations are gains or losses LO5 6-12

Market transactions may be affected by the endowment effect because: The seller has a tendency to demand a higher price The buyer has a tendency to offer a lower price LO5 6-13