Fundamental Principles of Managerial Economics- Incremental Principle, Marginal Principle

 

Managerial Economics is both conceptual and metrical. Before the substantive decision problems which fall within the purview of managerial economics are discussed, it is useful to identify and under­stand some of the basic concepts underlying the subject.

Economic theory provides several con­cepts and analytical tools which can be of considerable and immense help to a manager in taking many decisions and business planning. This is not to say that economics has all the solutions. In fact, actual problem-solving in business has found that there exists a wide disparity between the economic theory of the firm and actual observed practice.

Therefore, it would be useful to examine the basic tools of managerial economics and the nature and extent of the gap between the economic theory of the firm and the managerial theory of the firm. The contribution of economics to managerial economics lies in certain principles which are basic to managerial economics. There are six basic principles of managerial economics. They are:-

1. The Incremental Principle

The incremental concept is probably the most important in economics and is certainly the most frequently used in Managerial Economics. The incremental concept is closely related to the mar­ginal cost and marginal revenues of economic theory.

The two major concepts in this analysis are incremental cost and incremental revenue. The incremental cost denotes a change in total cost, whereas incremental revenue means a change in total revenue resulting from a decision of the firm.

The incremental principle may be stated as follows:

A decision is clearly a profitable one if

(i) It increases revenue more than costs.

(ii) It decreases some costs to a greater extent than it increases others.

(iii) It increases some revenues more than it decreases others.

(iv) It reduces costs more than revenues.

2. Marginal Principle

Marginal analysis implies judging the impact of a unit change in one variable on the other. Marginal generally refers to small changes. Marginal revenue is a change in total revenue per unit change in output sold. Marginal cost refers to the change in total costs per unit change in output produced (While incremental cost refers to the change in total costs due to a change in total output). The decision of a firm to change the price would depend upon the resulting impact/change in marginal revenue and marginal cost. If the marginal revenue is greater than the marginal cost, then the firm should bring about the price change.

3. The Opportunity Cost Principle

Both micro and macroeconomics make abundant use of the fundamental concept of opportunity cost. In everyday life, we apply the notion of opportunity cost even if we are unable to articulate its significance. In Managerial Economics, the opportunity cost concept is useful in decisions involving a choice between different alternative courses of action.

Resources are scarce, and we cannot produce all the commodities. For the production of one com­modity, we have to forego the production of another commodity. We cannot have everything we want. We are, therefore, forced to make a choice.

The opportunity cost of a decision is the sacrifice of alternatives required by that decision. The sacrifice of alternatives is involved when carrying out a decision that requires using a resource that is limited in supply with the firm. Opportunity cost, therefore, represents the benefits or revenue forgone by pursuing one course of action rather than another.

The concept of opportunity cost implies three things:

(i) The calculation of opportunity cost involves the measurement of sacrifices.

(ii) Sacrifices may be monetary or real.

(iii) The opportunity cost is termed the cost of sacrificed alternatives.

Opportunity cost is just a notional idea which does not appear in the books of account of the company. If a resource has no alternative use, then its opportunity cost is nil.

In managerial decision-making, the concept of opportunity cost occupies an important place. The economic significance of opportunity cost is as follows:

(i) It helps in determining the relative prices of different goods.

(ii) It helps in determining normal remuneration to a factor of production.

(iii) It helps in the proper allocation of factor resources.

4. Discounting Principle

This concept is an extension of the concept of time perspective. Since the future is unknown and incalculable, there is a lot of risk and uncertainty in future. Everyone knows that a rupee today is worth more than a rupee will be two years from now. This appears similar to the saying that “a bird in hand is more worth than two in the bush.” This judgment is made not on account of the uncertainty surround­ing the future or the risk of inflation.

It is simply that in the intervening period a sum of money can earn a return which is ruled out if the same sum is available only at the end of the period. In technical parlance, it is said that the present value of one rupee available at the end of two years is the present value of one rupee available today. The mathematical technique for adjusting for the time value of money and computing present value is called ‘discounting’.

5. Concept of Time Perspective Principle

The time perspective concept states that the decision maker must give due consideration both to the short-run and long-run effects of his decisions. He must give due emphasis to the various periods. It was Marshall who introduced the time element in economic theory.

The economic concepts of the long run and the short run have become part of everyday language. Managerial economists are also concerned with the short-run and long-run effects of decisions on revenues as well as costs. The main problem in decision-making is establishing the right balance between the long run and the short run.

In a short period, the firm can change its output without changing its size. In the long period, the firm can change its output by changing its size. In the short period, the output of the industry is fixed because the firms cannot change the size of the operation and they can vary only variable factors. In the long period, the output of the industry is likely to be more because the firms have enough time to increase their sizes and also use both variable and fixed factors.

In a short period, the average cost of a firm may be either more or less than its average revenue. In the long period, the average cost of the firm will be equal to its average revenue. A decision may be made based on short-run considerations, but may as time elapses have long-run repercussions which make it more or less profitable than it at first appeared.

6. Equi-Marginal Principle

One of the widest-known principles of economics is the equi-marginal principle. The principle states that input should be allocated so that value added by the last unit is the same in all cases. This generalization is popularly called the equi-marginal.

Let us assume a case in which the firm has 100 units of labour at its disposal. And the firm is involved in five activities viz., А, В, C, D and E. The firm can increase any one of these activities by employing more labour but only at the cost i.e., the sacrifice of other activities.

An optimum allocation cannot be achieved if the value of the marginal product is greater in one activity than in another. It would be, therefore, profitable to shift labour from low marginal value activity to high marginal value activity, thus increasing the total value of all products taken together.


Comments