Stratification of Skewed Populations: A review

When Dalenius provided a set of equations for the determination of stratum boundaries of a single auxiliary variable, that minimise the variance of the Horvitz–Thompson estimator of the mean or total under Neyman allocation for a fixed sample size, he pointed out that, though mathematically correct, those equations are troublesome to solve. Since then there has been a proliferation of approximations of an iterative nature, or otherwise cumbersome, tendered for this problem; many of these approximations assume a uniform distribution within strata, and, in the case of skewed populations, that all strata have the same relative variation. What seems to have been missed is that the combination of these two assumptions offers a much simpler and equally effective method of subdivision for skewed populations; take the stratum boundaries in geometric progression.     

Partnering relationships in construction: A literature review

There is no unified view as to what partnering relationships are in the construction industry. The purpose of this paper is to examine the literature in order to identify the main assumptions about partnering relationships in construction research and practice. The literature is compared to the Construction Industry Institute’s (CII, 1991) frequently cited definition of partnering as a long-term commitment between two or more parties in which shared understanding and trust develop for the benefits of improving construction. The literature review reveals a tendency to focus on project partnering in dyads between clients and contractors and there is also an emphasis on formal tools to develop these relationships, even if social aspects and relationship dynamics are recognised. The paper discusses these findings and suggests that, in order to increase the understanding of the substance and function of partnering relationships, it could be useful to incorporate knowledge from theoretical perspectives that are more in line with the CII definition. Two perspectives that seem particularly interesting in this respect are Supply Chain Management (SCM) and the Industrial Network Approach (INA), both of which focus on long-term relationships between actors beyond the dyad. INA also emphasises the informal aspects of relationship development. Incorporating these dimensions of partnering relationships requires processual and longitudinal studies, which are relatively rare in the contemporary partnering literature.     

The Maple computer algebra system: A review

We set out the main features of Maple V, Release 3, and discuss its potential value to econometricians. Computer algebra systems, of which Maple is a leading example, have developed with the increased power of modern computers, but require skill and patience to use. It seems likely they will find a place in the econometrician's toolkit for work at the interface between analytic and numerical work, where they should prove valuable. However, although Maple has many of the features of conventional statistical/econometric/numerical software, it should not be seen as a substitute.