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Modern efficiency measurement beings with Farrell (1957) who drew upon the

work of Debreu (1951) to define a simple measure of firm efficiency which

could account for multiple inputs. Worthington (2001) identifies three main

measures of efficiency; technical, allocative and economic. Technical efficiency

refers to use of productive resources in the most technologically efficient

manner - the maximum possible output from a given set of inputs. Within the

context of education, technical efficiency may then refer to the physical

relationship between the resources used (say, capital, labor and equipment)

and some education outcome. These educational outcomes may either be

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final education outcome (such as graduate employment rates, starting salaries

or acceptance rates into higher education) (p.245). Allocative efficiency is

concerned with choosing between different technically efficient combinations of

inputs used to produce the maximum possible outputs. Finally and when taken

together, allocative efficiency and technical efficiency determine the degree of

productive efficiency (also known as total economic efficiency) (p.245). Based

on the above description and when applied to the education sector it can be

said that, first, efficiency is about allocating efficiently between different kinds of

resources – e.g., between teachers and blackboards, or between more teachers per student and better-qualified teachers – that is, about choosing the most efficient input mix (allocative efficiency). Second, efficiency is also about

using each resource efficiently, that is, making the best use of each given input

(technical efficiency).

A number of analytical techniques have been developed to estimate the form

of cost and production frontier and associated inefficiency of individual

organizations. Green (1993) while giving an overview of techniques for

econometric analysis of technical (production) and economics (cost) efficiency

describes two broad paradigms for measuring economic efficiency. One based

on an essentially nonparametric, programming approach to analysis of

observed outcomes, and the other one based on an econometric approach to

estimation of theory-based models of production, cost, or profit. He further

elaborates that the empirical estimation of production and cost functions is a standard exercise in Econometrics. He says, ―the frontier production function or production frontier is an extension of the familiar regression model, based on

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or the convex conjugate of the two, the profit function, represents an ideal, the

maximum output attainable given a set of inputs, the minimum cost of

producing that output given the prices of the inputs, or the maximum profit

attainable given the outputs, and prices of the inputs‖ (p.92-93).

Thus, resultantly there are two basic approaches to the measurement of

efficiency: the statistical (or econometric) approach and the non-statistical (or

programming approach). The distinction between the two approaches derives

from the underlying assumptions. In summary, a method for measuring

efficiency can be statistical or no statistical, parametric or non-parametric,

deterministic or stochastic. Of the eight possible permutations of these

characteristics, the most common methods fall into one of three of these

categories: statistical parametric methods (deterministic or stochastic) and

deterministic non-statistical non-parametric methods (Johnes, 2004, p.625).

According to Zamorano (2004) the choice of estimation method has been an

issue of debate, with some researchers preferring the parametric and others

the non parametric approach. In his opinion, no approach is strictly preferable

to any other measurement of efficiency in education is definitely a complicated

issue. Several methodological approaches have been used to overcome

problems in educational efficiency measurement. They all have their

advantages and shortcomings. The early studies of educational production

function mostly used least-squares regression techniques. From the 1980s the

use of non-stochastic Data Envelopment Analysis (DAE) has become quite

common. DEA is a programming technique that envelopes the observed data

to determine the best practice frontier. This technique has become popular in

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multiple outputs, is nonparametric, and does not require input prices. An

alternative econometric approach (parametric and statistical techniques) has

progressed from ordinary least squares (OLS) regression to Stochastic Frontier

Analysis, where the simple ratio of one output to one input have been replaced

by composite ratios of efficiency derived from linear programming (LP)

methods.

4.5.1. Parametric techniques

Parametric techniques use econometric methods to estimate the parameters of

a specific functional form of cost or production function. There are a number of

methods that fall directly under this heading, including ordinary least squares

regression analysis and stochastic frontier analysis. Ordinary least squares

(OLS) are one of a variety of techniques that fall under the heading of

regression analysis. It involves the identification of a statistical relationship

between variables. OLS regression analysis fits a line of best fit to these points,

such that the line minimizes the sum of the squared vertical distances of the observed country‘s coasts. The line of best fit can be written as follows:

Ci= α + ßLi + ui

Where i represent the observations for different institutions, α is the fixed cost involved, β is the cost of educating another student, and µi is the regression residual (the difference between actual costs and those predicted by the line of

best fit).

A stochastic production frontier model were first introduced by Aigner et al.

(1977) and Meeusen and Van den Broeck (1977) and has been a significant

contribution to the econometric modeling of production and the estimation of

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components, one associated with the presence of technical efficiency and the

other being the traditional random error (Battese and Coelli, 1992, p.149). In

contrast OLS regression models implicitly assume that the whole of the residual

for a particular observation (in this context a country) is the result of genuine inefficiency. This decomposition of residuals between ‗error‘ and ‗genuine efficiency‘ provides a more accurate reflection of the true level of inefficiency. A number of studies have used these approaches to estimate the efficiency of

educational institutions. These include Sengupta (1987), Barrow (1991), Deller

and Rudnicki (1933), Cubbin and Zamani (1996) , Bates (1997), Moomaw

and Adkins (2005) and Kirjavainen (2007), details of last two are presented

in the later part of this chapter.

4.5.2. Non-parametric techniques

Non-Parametric techniques place no conditions on the functional form and use

observed data to infer the shape of the frontier. Most non-parametric methods

take the form of data envelopment analysis (DEA) and its many variants. DEA

essentially calculates the economic efficiency of a given organization relative to

the performance of other organizations producing the same good or service,

rather than against an idealized standard of performance. It is a nonstochastic

method in that it assumes all deviations from the frontier are the result of

inefficiency. It can be used as an alternative to regression-based techniques. It

does not involve statistical estimation, but instead makes use of linear

programming or some other form of mathematical programming methods to

characterize the set of efficient producers and then derive estimates of

efficiency for inefficient observations based on how far they deviate from the

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(1988), Ganely and Cubbin (1992), Beasley (1995) and Haksever and

Muragishi (1998) and others (for details see appendix 4-C) have applied these

approaches to educational institutions (Worthington, 2001, p.250).

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