Indifference Curves Economics

It is assumed in the analysis that a consumer always prefers a large number of a good to smaller amount of that good provided that the amount of other goods at his disposal remains unchanged. It implies that the consumer never reaches at satiety point. If the total satisfaction is to remain the same, the consumer must part with a diminishing number of bananas as he gets as increasing stock of oranges. The loss of satisfaction to the consumer on account of the downward movement must be made up by the gain through the rightward movement. As such the Indifference Curve must slope downwards to the right. Perfect complementary goods are used in a certain fixed ratio.

  • Figure 7.11 shows indifference curves drawn through each of the points we have discussed.
  • We know that a consumer is indifferent among the combinations lying on the same indifference curve.
  • This is so because Indifference Curves are assumed to be negatively sloping and convex to the origin.
  • The theory of consumption is based on the scale of preference and the ordinal ranks or orders of one’s preferences.
  • Bundles can contain many goods, but to simplify, we will consider only pairs of goods.

The assumption that is needed to ensure the existence of a utility function is that the preference relation be continuous. In order to ensure that we have indifference curves like those in Fig. As one moves along a straight-line indifference curve of perfect substitutes, marginal rate of substitution of one good for another remains constant. Examples of goods that are perfect substitutes are not difficult to find in the real world. For example, Dalda and Rath Vanaspati, two different brands of cold drink such as Pepsi Cola and Coca Cola are generally considered to be perfect substitutes of each other.

8.5 two indifference curves are shown cutting each other at point C. Now take point on indifference curve IC2 and point B on indifference curve IC1 vertically below A. Another important property of indifference curves is that they are usually convex to the origin. In other words, the indifference curve is relatively flatter in its right-hand portion and relatively steeper in its left-hand portion.

Indifference Map

Yet, two indifference curves need not be parallel to each other. The concept of indifference curve analysis was first propounded by British economist Francis Ysidro Edgeworth and was put into use by Italian economist Vilfredo Pareto during the early 20th century. However, it was brought into extensive use by economists J.R. IC analysis is based on the combinations of two commodities. Considering more than two commodities in IC analysis makes the calculations more complex.

  • Similarly, rate of decrease in consumption of coffee has gradually decreased even with constant increase in consumption of cigarette.
  • Higher the indifference curves, higher will be the level of satisfaction.
  • This is just as good to the consumer as a bundle with ten teaspoons of Morton salt and zero teaspoons of Diamond Crystal, as in bundle [latex]B[/latex].
  • The ability to predict with some accuracy the response of consumers to this policy is vital to determining the merits of the policy before millions of federal dollars are spent.
  • The marginal rate of substitu­tion on the contrary goes on diminishing.

This may further make it difficult to predict consumer behaviour. However, the market is full of a large number of commodities. Thus, it does not consider market behaviour in the analysis of consumer behaviour. For example, a change in the price of other commodities in the market may affect the purchase of the commodities being considered. The Indifference Curve IC thus is a locus of different combinations of two goods that yield the same level of satisfaction.

Two sets of earbuds and one iPod is no better than one set of earbuds and one iPod, so bundle [latex]B[/latex] lies on the same indifference curve. The same is true for two iPods and one set of earbuds, as in bundle [latex]C[/latex]. From this example, we can see that indifference curves for perfect complements have right angles. Economists use the vocabulary of maximizing utility to describe consumer choice. So far in the text, we have described the level of utility that a person receives in numerical terms. This section presents an alternative approach to describing personal preferences, called indifference curve analysis, which avoids the need for using numbers to measure utility.

Indifference Schedule:

According to this theory, utility is a psychological phenomenon and thus it is unquantifiable. However, the theory assumes that a consumer can express utility in terms of rank. Consumer can rank his/her preferences on the basis of satisfaction yielded from each combination of goods. Hicks and Allen criticized Marshallian cardinal approach of utility and developed indifference curve theory of consumer’s demand.

Indifference Curves Cannot Intersect

Marginal utility refers to the utility gained from the consumption of an additional unit of a good or service. Here, we understand that all three products resting in the indifferent curve give him the same satisfaction. However, his preference for those combined products can be arranged in the order of preference. In short, the consumer always prefers more of both commodities to less.

3 Properties of Indifference Curves

Similarly, any points on the middle indifference curve Um provide greater utility than any points on the lowest indifference curve Ul. An indifference curve is a chart showing various combinations of two goods or commodities that consumers can choose. At any point on the curve, the combination of the two will leave the consumer equally well off or equally satisfied—hence indifferent. This axiom implies that points in the indifference set for X (if there are any besides X) must lie in areas A and C. This is because a higher indifference curve implies a higher level of satisfaction. Therefore, all combinations on IC1 offer the same satisfaction, but all combinations on IC2 give greater satisfaction than those on IC1.

That changes the horizontal intercept of the budget line; if she spends all of her money on horseback riding, she can now ride 10 days per semester. Another way to think about the new budget line is to remember that its slope is equal to the negative of the price of the good on the horizontal axis divided by the price of the good on the vertical axis. When the price of horseback riding (the good on the horizontal axis) goes down, the budget line becomes flatter. Ms. Bain picks a new utility-maximizing solution at point Z. The assumption that consumers prefer variety is not necessary but still applies in many situations.

When one indifference curve crosses the budget line in two places, however, there will be another, higher, attainable indifference curve sitting above it that touches the budget line at only one point of tangency. For example, each indifference curve is typically convex to the origin, and no two indifference curves ever intersect. Consumers are always assumed to be more satisfied when achieving bundles of goods on indifference curves that are farther from the origin. The above figure shows the downward-sloping indifference curve. When the consumer moves from point A to B, the quantity of Y commodity decreases from Y1 to Y1, and at the same time, the number of X increases from X1 to X2 keeping the same level of satisfaction.

Browse more Topics under Theory Of Consumer Behavior

Other names for the indifference curve are the Iso-utility curve; Equal utility curve. Suppose the ration packages given to all prisoners contained the same amounts of both coffee and tea. But notice that for typical British prisoners, given indifference curves which reflect their general preference for tea, the MRS at the initial allocation (point A) is less than the price ratio. For French prisoners, the MRS is greater than the price ratio (point B). By trading, both British and French prisoners can move to higher indifference curves.

What is Cardinal and Ordinal Utility? Assumptions

Hence, an indifference curve to the right always embodies a higher level of fulfillment. Because of this reason, the consumer always attempts to move outward to maximize his level of satisfaction. Indifference curves (ICs) are at all times convex to the origin due to the fact of diminishing marginal rate of substitution. The marginal rate of substitution of one commodity for another reduces or diminishes when more and more of one commodity is substituted for another.

If a good satisfies all four properties of indifference curves, the goods are referred to as ordinary goods. In the above figure, the quantity of good X is measured along the X-axis, and the quantity of good Y is measured along Y-axis. IC is the indifference curve which shows the different combinations of goods X and Y. All the combinations of both goods on the IC yield the same level of satisfaction to the consumer. Thus, if we take the locus of all these points, we get a curve showing various blends of at least two commodities that yields an equal level of pleasure to the buyers. With this preference ordering, no two distinct bundles are indifferent; indifferent sets are singletons.

Such a situation is encountered when the difference in utility between two points Y and X is so small that even a rational consumer cannot perceive it, i.e., feel the difference. This is why we get an indifference region rather than an indifference curve. Most of the goods are imperfect substitutes for one another.

If bundle A represents more of at least one good and no less of any other good than bundle B, then A is preferred to B. Recall that we are assuming that the tax credit will cause the average fuel economy of US cars to double. So from a consumer behavior perspective, one of the things we want to know in evaluating the policy is whether this improvement in gas mileage will cause an equivalent decrease in the demand for gasoline. In other words, the consumer decision is about the trade-off of purchasing gasoline to travel in a car versus all the other uses of the money spent on gas. Where [latex]\Delta[/latex] indicates a change in the quantity of the good.

Now, of course, it’s not always that simple, but in basic economic theory, we can assume that consumers have a preference for larger quantities. The higher the indifference curves are, the larger the quantities of both goods. The slope of the indifference curve at any point is the negative marginal utility of good A as a proportion of the marginal utility of good B. It indicates that the optimal consumption bundle – the marginal rate of substitution between goods A and B – is the ratio of their prices. The principle of diminishing marginal utility is illustrated here as the total utility increases at a diminishing rate with additional consumption. It is evidenced by figures D, E, and F having decreased marginal utility.