Almost sure convergence for weighted sums of pairwise PQD random variables

We obtain Marcinkiewicz-Zygmund strong laws of large numbers for weighted sums of pairwise positively quadrant dependent random variables stochastically dominated by a random variable $X \in \mathscr{L}_{p}$, $1 \leqslant p < 2$. We use our results to establish the strong consistency of estimators which emerge from regression models having pairwise positively quadrant dependent errors.Comment: 20 page

Searching, Matching and Education: a Note

In this paper the individual optimal level of education is set in a frictional labor market, where matching is not perfect. Also search frictions are a function of the average education can improve economic efficiency, not only through improvements in workers productivity, but also making the matching process more efficient, and thus reducing the unemployment level.Education, Externalities, Search, Matching, Unemployment.

Young Employment, Job-Skill Composition and Minimum Wages: Evidence from a 'Natural Experiment'

Empirically very little is known about the impact of an increase in the minimum wage of young workers on the job-skill composition. This is an important question because small (or zero) effects on teenage employment may mask a substitution of more for less-skilled teenagers. Therefore, the estimation of the elasticity of substitution between skilled and unskilled workers is required. This paper will consider the increase in the minimum wage of young workers that took place in Portugal on the 1st January, 1987. This change is of particular interest, not only because it was so large (33% in real terms) and affected a significant share of workers under 20 years old (about 20%), but also because it motivated a decrease in the wage premium earned by young skilled workers from 1.24 to 1.20. The results are consistent with the view that the minimum wage increase had some negative impact on employment of unskilled workers, the most affected group: an increase of 1% in wage induced by the increase in minimum wage reduces employment of this group of workers between 0.42% to 0.47%. Nevertheless, this negative impact was partially compensated by the substitution of more for less-skilled teenagers, because there is some evidence that the elasticity of substitution between young workers with different skills is different from zero.

Induced pluripotent stem cells, a giant leap for mankind therapeutic applications

Induced pluripotent stem cells (iPSC) technology has propelled the field of stem cells biology, providing new cells to explore the molecular mechanisms of pluripotency, cancer biology and aging. A major advantage of human iPSC, compared to the pluripotent embryonic stem cells, is that they can be generated from virtually any embryonic or adult somatic cell type without destruction of human blastocysts. In addition, iPSC can be generated from somatic cells harvested from normal individuals or patients, and used as a cellular tool to unravel mechanisms of human development and to model diseases in a manner not possible before. Besides these fundamental aspects of human biology and physiology that are revealed using iPSC or iPSC-derived cells, these cells hold an immense potential for cell-based therapies, and for the discovery of new or personalized pharmacological treatments for many disorders. Here, we review some of the current challenges and concerns about iPSC technology. We introduce the potential held by iPSC for research and development of novel health-related applications. We briefly present the efforts made by the scientific and clinical communities to create the necessary guidelines and regulations to achieve the highest quality standards in the procedures for iPSC generation, characterization and long-term preservation. Finally, we present some of the audacious and pioneer clinical trials in progress with iPSC-derived cells.info:eu-repo/semantics/publishedVersio

Agreeing to disagree in a countable space of equiprobable states

An example is given in which agents agree to disagree, showing that Aumann's (1976) Agreement Theorem does not extend to a countable space of equiprobable states of nature. Even in this unorthodox setting, if the sets of the information partitions are intervals, an agreement theorem holds. A result that describes the margin for disagreement is also obtained.Agreeing to disagree, Interactive epistemology, Bounded rationality.

A stochastic spreadsheet model analysing investment options for the development of pasture on beef cattle farms : a dissertation submitted in partial fulfilment of the requirements for the degree of Master in Applied Science at Massey University

The decision to proceed with farm development to increase animal production is complex. Standalone personal computer software to study either the financial or physical aspects of farm development is available, but models which integrate these components and account for the risks associated with the investment are not. A stochastic spreadsheet (Microsoft Excel®) model was therefore developed to predict the profitability, feasibility and risk of pasture development for two case farms: one in southern Brazil and the other near Wanganui in New Zealand. Pasture was developed at different rates for each farm and the model was used to predict the associated physical and financial changes over-time and a probability distribution of the net present values (NPV) of the net operating profit after tax and before interest (NOPAT) relative to the status quo situation. The extra pasture was used solely for increasing beef cattle production. On the Brazilian case farm the development of 2,263 ha at two rates was studied. The continuation of the status quo had first degree stochastic dominance in terms of the NPV over both development rates; it was superior by about NZ$46.000 for the 200 ha/y option and ca. NZ$ 110.000 for the 500 ha/y option at a 16% discount rate. However, at a 6% discount rate the 500 ha/y development rate had first degree stochastic dominance in terms of the NPV over both the continuation of the status quo (by about NZ$960.000) and the 200 ha/y option (ca. NZ$ 120.000). This indicates that pasture development could proceed profitability if interest rates continue to fall in Brazil as predicted. For the New Zealand case farm the development of 247 ha at 50 ha/y had first degree stochastic dominance over the 25 ha/y (ca. NZ$24,000) and continuation of the status quo (ca. NZ$ 208.000) at a 6% discount rate. Pasture development should therefore continue. Stochastic analysis of the pasture development investment options gave a better insight into the likely outcomes for a project, and provides the farmer with more information for making a decision on whether, and how. to proceed with farm development. The model could easily be adapted for studying farm development with respect to other types of livestock enterprises Keywords: pastures, development, risk, feasibility, profitability, model