No Can Do?: A test of the textbook model of labour markets.

This paper first provides a twofold test of the Card and Lemieux [2001] hypothesis that variation in college attainment growth rates can have a substantial impact on cohort specific returns to college. Most importantly, this study exploits Britain’s expansion of its higher education system between 1988 and 1994 to show that the recent increase in college attainment growth rates has decreased college premiums for Britain’s youngest workers. This is in line with the predictions from an adverse supply shock in a simple aggregate model of relative demand for and supply of college labor. Moreover, this paper conjectures that a simple demand-supply model can go a substantial distance towards explaining the variation in the UK economy-wide average return to college and overall wage inequality.Labour market; Market; Markets; Model;

Semi-bayesian D-optimal designs and estimation procedures for mean and variance functions.

Semi-Bayesian D-optimal designs for fitting mean and variance functions are derived for some prior distributions on the variance function parameters. The impact of the mean of the prior and of the uncertainty about this mean is analyzed. Simulation studies are performed to investigate whether the choice of design has a substantial impact on the efficiency of the mean and the variance function parameter estimation and whether the D-optimality criterion is appropriate irrespective of the method applied to estimate the variance function parameters.Functions;

The impact of payroll tax reductions on employment and wages: A natural experiment using firm level data.

Labour market; Market; Markets; Model; Impact; Employment; Firm level data; Data;

Exploiting correlation in the construction of D-optimal response surface designs.

Cost considerations and difficulties in performing completely randomized experiments often dictate the necessity to run response surface experiments in a bi-randomization format. The resulting compound symmetric error structure not only affects estimation and inference procedures but it also has severe consequences for the optimality of the designs used. Fir this reason, it should be taken into account explicitly when constructing the design. In this paper, an exchange algorithm for constructing D-optimal bi-randomization designs is developed and the resulting designs are analyzed. Finally, the concept of bi-randomization experiments is refined, yielding very efficient designs, which, in many cases, outperform D-optimal completely randomized experiments.Structure;

The D-optimal design of blocked and split-plot experiments with mixture components.

So far, the optimal design of blocked and split-plot experiments involving mixture components has received scant attention. In this paper, an easy method to construct efficient blocked mixture experiments in the presence of fixed and/or random blocks is presented. The method can be used when qualitative variables are involved in a mixture experiment as well. It is also shown that orthogonally blocked mixture experiments are highly inefficient compared to D-optimal designs. Finally, the design of a split-plot mixture experiment with process variables is discussed.Design; Fixed and random blocks; Minimum support design; Mixture experiment; Optimal; Optimal design; Orthogonal blocking; Process variables; Processes; Qualitative variables; Split-plot experiment; Variables;

Outperforming completely randomized designs.

Bi-randomization designs have become increasingly popular in industry because some of the factors under investigation are often hard-to-change. It is well-known that the resulting compound symmetric error structure not only affects estimation and inference procedures but also the efficiency of the experimental designs used. In this paper, the use of bi-randomization designs is shown to outperform completely randomized designs in terms of D-efficiency. This result suggests that bi-randomization designs should be considered as an alternative to completely randomized designs even if all experimental factors are easy-to-change.Optimal;

Dangerous liaisons: a social network model for the gender wage gap

We combine stylized facts from social network literature with findings from the literature on the gender wage gap in a formal model. This model is based on employers’ use of social networks in the hiring process in order to assess employee productivity. As a result, there is a persistent gender wage gap, with women being underpaid relative to men after controlling for productivity characteristics. Networks exhibit inbreeding biases by productivity and by gender, which in combination with women’s lower network density cause women to be hired less often through referral, as well as receive a lower average referral wage premium. Finally, we use 2001-2006 UK Labour Force Survey data to test the hypotheses implied by our model. We find that networks do indeed account for a significant part of the gender wage gap for newly hired workers.social networks, gender wage gap, imperfect information

Auditing the Numeracy Demands of the Middle Years Curriculum

The National Numeracy Review Report recognized that numeracy development requires an across the curriculum commitment. To explore the nature of this commitment we conducted a numeracy audit of the South Australian Middle Years curriculum, using a numeracy model that incorporates mathematical knowledge, dispositions, tools, contexts, and a critical orientation. All learning areas in the published curriculum were found to have distinctive numeracy demands. The audit should encourage teachers to promote numeracy in even richer ways in the curriculum they enact with students

Weak measurement of the Goos-Hanchen shift

It is well known from quantum mechanics that weak measurements offer a means of amplifying and detecting very small phenomena. We present here the first experimental observation of the Goos-Hanchen shift via a weak measurement approach