competitive tender an invitation for private sector firms to submit TENDERS (price bids) for contracts to supply goods or services to the public sector which the public sector has traditionally supplied for itself. Competitive tendering seeks to introduce competition in the provision of goods or services and thus reduce the costs to government departments, local authorities and health authorities. See DEREGULATION.
competitor a business rival of a firm supplying a good or service that offers buyers an identical or similar product. See COMPETITION, COMPETITIVE ADVANTAGE, COMPETITIVE STRATEGY, PRODUCT DIFFERENTIATION.
complementary products GOODS or SERVICES whose demands are interrelated (a joint demand) so that an increase in the price of one of the goods results in a fall in the demand for the other. For example, if the price of tennis rackets goes up, this results not only in a decrease in the demand for rackets but, because less tennis is now played, a fall also in the demand for tennis balls. See SUBSTITUTE PRODUCTS, CROSS-ELASTICITY OF DEMAND.
complete contract see CONTRACT.
complex monopoly a situation defined by UK COMPETITION POLICY as one in which two or more suppliers of a particular product restrict competition between themselves. ‘Complex monopoly’ in essence refers to an OLIGOPOLY situation where the firms concerned, although pursuing individual (i.e. non-collusive) policies, nonetheless behave in a uniform manner and produce a result that is non-competitive (i.e. similar to COLLUSION). The problem is that it is often difficult to distinguish between competitive and non-competitive situations. For example, if firms charge identical prices, is this reflective of competition (i.e. prices that are brought together because of competition) or a deliberate suppression of competition?
compound interest the INTEREST on a LOAN that is based not only on the original amount of the loan but the amount of the loan plus previous accumulated interest. This means that, over time, interest charges grow exponentially; for example, a £100 loan earning compound interest at 10% per annum would accumulate to £110 at the end of the first year and £121 at the end of the second year, etc., based on the formula: compound sum = principal (1 + interest rate) number of periods
that is, 121 = 100 (1 + 0.1)2.
Compare SIMPLE INTEREST.
computer an electronic/electromechanical device that accepts alphabetical and numerical data in a predetermined form, stores and processes this data according to instructions contained in a computer program, and presents the analysed data.
Computers have dramatically improved the productivity of data processing in commerce and business; for example, computer-aided design and computer-aided manufacturing systems have improved the speed and cost with which new components or products can be assigned and subsequently scheduled for production; computer-aided distribution and stock control systems such as ELECTRONIC POINT OF SALE (EPOS) have helped to minimize stockholdings and have improved customer services; computers have rapidly taken over the manual tasks of keeping accounting records such as company sales and payroll. Computers have also played a prominent role in speeding up the response of commodity and financial markets to changing demand and supply conditions by processing and reporting transactions quickly.
In recent years computers have underpinned the rapid expansion of E-COMMERCE using the INTERNET. See STOCK EXCHANGE, AUTOMATION, MASS PRODUCTION.
concealed unemployment see DISGUISED UNEMPLOYMENT.
concentration measures
The measures of the size distribution of firms engaged in economic activities.
The broadest concentration measure is the aggregate concentration measure, which looks at the share of total activity in an economy accounted for by the larger firms, for example, the proportion of total industrial output accounted for by the largest 200 firms; or the share of total manufacturing output produced by the 100 largest companies. Various size criteria may be used for this measure, in particular, sales, output, numbers employed and capital employed, each of which can give slightly different results because of differences in capital intensity. Such measures serve to give an overall national view of concentration and how it is changing over time.
Although aggregate concentration measures are useful, they are generally too broad for purposes of economic analysis where interest focuses upon markets and performance in these markets. Consequently, economists have developed several measures of MARKET concentration that seek to measure SELLER or BUYER CONCENTRATION. The most common of these measures is the CONCENTRATION RATIO, which records the percentage of a market’s sales accounted for by a given number of the largest firms in that market. In the UK it has been usual to estimate the concentration ratio for the three or (more recently) five largest firms, whereas in the USA the four-firm concentration ratio tends to be employed.
Fig. 28 Concentration measures. (a) Cumulative concentration curves, showing the cumulative share of market size accounted for by various (cumulative) numbers of firms. (b) The Lorenz curve shows the cumulative share of market size on one axis accounted for by various (cumulative) percentages of the number of firms in the market.
The concentration ratio, however, records only seller concentration at one point along the cumulative concentration curve, as Fig. 28 (a) indicates. This makes it difficult to compare concentration curves for two different markets, like A and B in the figure, where their concentration curves intersect. For example, using a three-firm concentration ratio, market A is more concentrated while using a five-firm ratio shows market B to be more concentrated. An alternative concentration index, called the HERFINDAHL INDEX, gets around this problem by taking into account the number and market shares of all firms in the market. The Herfindahl index is calculated by summing the squared market shares of all firms. The index can vary between a value of zero (where there are a large number of equally sized firms) and one (where there is just one firm).
Concentration measures, like the concentration ratio and the Herfindahl index, are known as absolute concentration measures since they are concerned with the market shares of a given (absolute) number of firms. By contrast, relative concentration measures are concerned with inequalities in the share of total firms producing for the market. Such irregularities can be recorded in the form of a Lorenz curve as in Fig. 28 (b). The diagonal straight line shows what a distribution of complete equality in firm shares would look like, so the extent to which the Lorenz curve deviates from this line gives an indication of relative seller concentration. For example, the diagonal line shows how we might expect 50% of market sales to be accounted for by 50% of the total firms, whilst in fact 50% of market sales are accounted for by the largest 25% of total firms, as the Lorenz curve indicates. The Gini coefficient provides a summary measure of the extent to which the Lorenz curve for a particular market deviates from the linear diagonal. It indicates the extent of the bow-shaped area in the figure by dividing the shaded area below the Lorenz curve by the area above the line of equality. The value of the Gini coefficient ranges from zero (complete equality) to one (complete inequality).
In practice, most market concentration studies use concentration ratios calculated from data derived from the census of production.
Concentration measures are widely used in economic analysis and for purposes of applying COMPETITION POLICY to indicate the degree of competition or monopolization present