Factors of production in the short run and in the long run

2. Classification and structure of costs of the firm

In the long-term period all desirable changes in quantity and structure of all resources can be carried out both separate firm, and branch as a whole. For this period the firm can change capacity of the equipment, its quantity, master a new kind of production or even at all to leave from the market. Therefore here all resources are variables. And the firm chooses that which will allow it to make production with the minimal average costs from available technologies

Firms seek to maximize their profits, i.e. they attempt to produce as cheaply as possible. Thus, profit ( π ) can be defined in terms of revenue and costs. Revenue (R) is what the firm earns by selling goods or services in a given period such as a year. Costs (C) are the expenses which are necessary for producing and selling goods or services during the period. Profit is the total revenue (TR) from selling the output minus the total costs (TC) of inputs used:

π = TR – TC

Economic Profit occurs when total revenue exceeds total cost. The revenue of the firm more than covers all opportunity cost. After paying the explicit cost and accounting for the implicit cost, the firm has revenue left over. This remaining revenue is economic profit.

The normal profit - the minimal payment necessary to keep enterprise ability within the limits of the given activity. If compensation for enterprise work will appear below this size that the businessman will be switched to other, more attractive activity.

Profit is an absolute indicator that illustrates how efficient the production of the firm is. If we measure the efficiency of costs per a unit of output, we will know how profitable the firm is, in other words, the profitability = profit / costs. For example, if the profits are 15 money units and costs are 100 money units, then the profitability is 0.15 (15%).

Marginal revenue (MR) is the corresponding change in total revenue from selling one more unit of output.

The actual length of the short run will differ from firm to firm. If it takes a farmer a year to buy new land, buildings and equipment, the short run is any time up to a year, and the long run is any time period longer than a year. On the other hand, if it takes a shipping company three years to obtain an extra ship, the short run is any

period up to three years, and the long run is any period longer than three years.

Firms seek to maximize their profits, i.e. they attempt to produce as cheaply as possible. Thus, profit ( π ) can be defined in terms of revenue and costs. Revenue (R) is what the firm earns by selling goods or services in a given period such as a year. Costs (C) are the expenses which are necessary for producing and selling goods or services during the period. Profit is the total revenue (TR) from selling the output minus the total costs (TC) of inputs used:

π = TR – TC where π – a Greek letter ‘pi’represents profits.

Profit is an absolute indicator that illustrates how efficient the production of the firm is. If we measure the efficiency of costs per a unit of output, we will know how profitable the firm is, in other words, the profitability = profit / costs. For example, if the profits are 15 money units and costs are 100 money units, then the profitability is 0.15 (15%).

Costs (C) are the expenses which are necessary for producing and selling goods or services during the period.

Costs should include opportunity costs of all resources used in production. Opportunity cost of a commodity is the amount obtained by an input in its best alternative use. In particular, costs include the owner’s time and effort in running the business. Costs also include the opportunity cost of the financial capital used in the firm.

Factors not owned by the firm are called explicit costs. They are direct payments to outside suppliers of inputs, for example, payments for electricity. Factors already owned by the firm are called implicit costs. They are the costs that do not involve a direct payment of money to a third party, but which nevertheless involve a sacrifice of some alternative. For example, the firm owns machinery and it does not have to pay for using them. Their opportunity costs are thus implicit costs.

Aiming to get higher profits, firms obtain each output level as cheaply as possible. Firms choose the optimal output level to receive the highest profits. This decision can be described in terms of marginal cost and marginal revenue.

Marginal cost (MC) is an increase in total cost when oneadditional unit of output is produced.

Marginal revenue (MR) is the corresponding change in totalrevenue from selling one more unit of output.

As the individual firm has to be a price-taker, each firm’s marginal revenue is the prevailing market price. Profits are the highest at the output level at which marginal cost is equal to marginal revenue, that is, to the market price of the output. If profits are negative at this output level, the firm should close down.

An increase in marginal cost reduces output. A rise in marginal revenue increases output. Of course, the optimal quantity supplied is affected by such noneconomic factors as technology, environment, etc.

Other cost concepts are average cost (AC) and averagetotal cost (ATC), average fixed cost (AFC) and average variable cost (AVC). If Q represents the quantity of output produced, these concepts can be defined as follows:

AFC = TFC/Q: AVC = TVC/Q; ATC = TC/Q; ATC = AFC + AVC