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41.
Unemployment has been identified as one of the main problems confronting South Africa. Recently, in order to improve rural infrastructure and create employment, several pilot projects of rural road construction have been initiated in South Africa. In such a context it is considered that attention should be drawn to a pilot project carried out some time ago in Botswana to examine the potential of labour‐intensive methods in the construction and maintenance of rural roads.

The main conclusion of the pilot project was that labour‐intensive methods were viable, although attention had to be paid to several critical factors. In 1982, following its evaluation of the pilot project, the Government of Botswana decided that over the next five years the technical and organisational methods developed during the pilot project should be replicated throughout Botswana.

After a brief survey of the background to the project, the paper summarises several important features of the pilot project and its main findings. The paper closes with some comments on the implications of this pilot project for those currently underway in South Africa.  相似文献   

42.
Pacific Presbyterian Medical Center has chalked up an impressive string of successes. What's ahead? A $20 million cancer center.  相似文献   
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Abstract  The tables for the Friedman rank-test arc extended using a sampling method. A table is given for the traditional significance levels .01, .025, .05 and .10 for number of blocks equal to 7 and 8 and for treatments of size 6 and 7. A brief discussion of available tables is also included along with an example of an application.  相似文献   
46.
The case is investigated when Hoeffding's one sample U–statistic theorem for the sample variance S2 is not applicable. It is shown that this occurs only when the parent distribution is the two–point distribution with jumps of equal magnitude. For this exceptional case the standardised S2 is shown to converge in distribution to (1 – V )√2, where V has chi–square distribution with one degree of freedom.  相似文献   
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In our earlier paper [Srivastava, Agnihotri and Dwivedi (1980)] the dominance of double k-class over k-class with respect to exact mean squared error matrix criteria is established. It is observed that given a member of k-class, one can pick up a member of double k-class that will provide an improved estimator of the coefficients. This result prompted us to study the exact finite sample properties of the double k-class estimator. For this, we have considered a structural equation containing two endogenous variables and have investigated the properties of double k-class estimators of the coefficients of explanatory endogenous variables assuming characterizing scalars to be non-stochastic.  相似文献   
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Prof. Dr. T. Royen 《Metrika》1990,37(1):145-154
Summary It is proved that for any fixed argument the sequence (P k) of the distribution functions of the ranges ofk i.i.d. univariate random variables is log-concave if the random variables have a log-concave density. If the support of the distribution is an infinite interval and the density is monotonous then the theorem holds also with “log-convex” instead of “log-concave”. The resulting inequalities can be used by a quick algorithm for closed maximum range test procedures for all pairwise comparisons (Royen 1988, 1989a, 1989b). Under the above assumptions the application of this algorithm can be extended e.g. to pairwise comparisons of variances.  相似文献   
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We present a formalism which makes explicit and precise the confirming effect of multiple observers and repeated trials on composite ratings, considering the relevant subjective inputs.  相似文献   
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