Allelic proportions of 16 STR loci-including the new European Standard Set (ESS) loci-in a Swiss population sample.

Allele frequencies and forensically relevant population statistics of 16 STR loci, including the new European Standard Set (ESS) loci, were estimated from 668 unrelated individuals of Caucasian appearance living in different parts of Switzerland. The samples were amplified with a combination of the following three kits: AmpFlSTR® NGM SElect?, PowerPlex® ESI17 and PowerPlex® ESX 17. All loci were highly polymorphic and no significant departure from Hardy-Weinberg equilibrium and linkage equilibrium was detected after correction for sampling.

A new method for constructing exact tests without making any assumptions

We present a new method for constructing exact distribution-free tests (and confidence intervals) for variables that can generate more than two possible outcomes.This method separates the search for an exact test from the goal to create a non-randomized test. Randomization is used to extend any exact test relating to meansof variables with finitely many outcomes to variables with outcomes belonging to agiven bounded set. Tests in terms of variance and covariance are reduced to testsrelating to means. Randomness is then eliminated in a separate step.This method is used to create confidence intervals for the difference between twomeans (or variances) and tests of stochastic inequality and correlation.

A mathematical excursion: From the three-door problem to a Cantor-type perfect set

We start with a generalization of the well-known three-door problem:the n-door problem. The solution of this new problem leads us toa beautiful representation system for real numbers in (0,1] as alternated series, known in the literature as Pierce expansions. A closer look to Pierce expansions will take us to some metrical properties of sets defined through the Pierce expansions of its elements. Finally, these metrical properties will enable us to present 'strange' sets, similar to the classical Cantor set.

Improved nonparametric confidence intervals in time series regressions

Condence intervals in econometric time series regressions suffer fromnotorious coverage problems. This is especially true when the dependencein the data is noticeable and sample sizes are small to moderate, as isoften the case in empirical studies. This paper suggests using thestudentized block bootstrap and discusses practical issues, such as thechoice of the block size. A particular data-dependent method is proposedto automate the method. As a side note, it is pointed out that symmetricconfidence intervals are preferred over equal-tailed ones, since theyexhibit improved coverage accuracy. The improvements in small sampleperformance are supported by a simulation study.

A tractable consideration set structure for network revenue management

Models incorporating more realistic models of customer behavior, as customers choosing from an offerset, have recently become popular in assortment optimization and revenue management. The dynamicprogram for these models is intractable and approximated by a deterministic linear program called theCDLP which has an exponential number of columns. When there are products that are being consideredfor purchase by more than one customer segment, CDLP is difficult to solve since column generationis known to be NP-hard. However, recent research indicates that a formulation based on segments withcuts imposing consistency (SDCP+) is tractable and approximates the CDLP value very closely. In thispaper we investigate the structure of the consideration sets that make the two formulations exactly equal.We show that if the segment consideration sets follow a tree structure, CDLP = SDCP+. We give acounterexample to show that cycles can induce a gap between the CDLP and the SDCP+ relaxation.We derive two classes of valid inequalities called flow and synchronization inequalities to further improve(SDCP+), based on cycles in the consideration set structure. We give a numeric study showing theperformance of these cycle-based cuts.

Solving two production scheduling problems with sequence-dependent set-up times

In today’s competitive markets, the importance of goodscheduling strategies in manufacturing companies lead to theneed of developing efficient methods to solve complexscheduling problems.In this paper, we studied two production scheduling problemswith sequence-dependent setups times. The setup times areone of the most common complications in scheduling problems,and are usually associated with cleaning operations andchanging tools and shapes in machines.The first problem considered is a single-machine schedulingwith release dates, sequence-dependent setup times anddelivery times. The performance measure is the maximumlateness.The second problem is a job-shop scheduling problem withsequence-dependent setup times where the objective is tominimize the makespan.We present several priority dispatching rules for bothproblems, followed by a study of their performance. Finally,conclusions and directions of future research are presented.

Evaluating predictive densities of U.S. output growth and inflation in a large macroeconomic data set

We evaluate conditional predictive densities for U.S. output growth and inflationusing a number of commonly used forecasting models that rely on a large number ofmacroeconomic predictors. More specifically, we evaluate how well conditional predictive densities based on the commonly used normality assumption fit actual realizationsout-of-sample. Our focus on predictive densities acknowledges the possibility that, although some predictors can improve or deteriorate point forecasts, they might have theopposite effect on higher moments. We find that normality is rejected for most modelsin some dimension according to at least one of the tests we use. Interestingly, however,combinations of predictive densities appear to be correctly approximated by a normaldensity: the simple, equal average when predicting output growth and Bayesian modelaverage when predicting inflation.

Controlo interno na prevenção de erros e fraudes

Atualmente, as situações de erros e fraudes, têm ocorrido com muita frequência a nível mundial. Por exemplo em Cabo Verde estas têm vindo a ganhar espaço nos mídias, onde a todo momento aparece casos de erros e fraudes, como por exemplo, os casos da Sociedade Cabo-verdiana de Tabacos, Banco Comercial do Atlântico, Caixa Económica, Câmara Municipal da Ribeira Brava, Associação Sport Club Moreirense, Sociedade de Segurança Industrial, Marítima e Comercial, Ministério das Finanças entre outros. Essas situações desfavoráveis para qualquer empresa, são derivadas de uma gestão menos cuidada dos recursos, e dos valores e princípios éticos cultivados pelas pessoas. O triângulo de fraude criada por Donald Cressey demonstra os motivos que leva um individuo a cometer atos fraudulentos, como sendo a motivação, a pressão e a oportunidade. Neste sentido, o controlo interno surge como uma ferramenta muito importante e fundamental para mitigar os riscos advenientes da ocorrência de erros e fraudes, suscetíveis de acontecer nas empresas. O controlo interno traduz num conjunto de medidas que protegem o património da empresa e garantem o cumprimento dos seus objetivos entretanto, como qualquer outra ferramenta de gestão está possui determinadas limitações que podem ser ultrapassadas com a utilização de alguns procedimentos básicos e, ou alternativos de controlo interno. É imprescindível que um sistema de controlo interno, para além de implementado, adequado e em funcionamento, seja mantido e acompanhado. O estudo dos casos da SILMAC, SA e da SCT, SA, mostram a importância que o controlo interno tem na prevenção e deteção de erros e fraudes, pois denota-se que as fraudes cometidas aconteceram na sequência de fraquezas de controlo interno e no excesso de confiança depositada nos colaboradores. Currently, the situations of errors and fraud have occurred very often in the world. Cape Verde in these situations have gained ground in the media, where every moment appears to errors and fraud cases, such as cases of “Sociedade cabo-verdiana de tabacos, Banco Comercial do Atlântico, Caixa Económica, Câmara Municipal da Ribeira Brava, Associação Sport Club Moreirense, Sociedade de segurança industrial, marítima e comercial, Ministério de finanças” amongst others. These situations which unfavorable for any company, are derived from a less carefully management of resources and ethical principles and values cultivated by people. The fraud triangle created by Donald Cressey, demonstrates reasons that lead an individual to commit fraudulent acts, such as motivation, opportunity and pressure. In this sense, internal control emerges as a very important tool to mitigate the risks arising from situations of errors and fraud, which are likely to happen in companies. The internal control translates into a set of measures that protect the assets of the business and ensure the fulfillment of its objectives however, like any other management tool is has limitations, however these can be overcome with the use of basic procedures, or alternative internal control. It is essential that an internal control system, in addition to implemented, adequate and functioning is maintained and monitored. The case studies of SILMAC and SCT, show the importance of internal control is the prevention and detection of errors and fraud. For note that the fraud occurred following oversights in its internal control and confidence in their employees.

Entrepreneurial success and failure: Confidence and fallible judgement

Excess entry or the high failure rate of market-entry decisions is often attributed tooverconfidence exhibited by entreprene urs. We show analytically that whereas excess entryis an inevitable consequence of imperfect assessments of entrepreneurial skill, it does notimply overconfidence. Judgmental fallibility leads to excess entry even when everyone isunderconfident. Self-selection implies greater confidence (but not necessarilyoverconfidence) among those who start new businesses than those who do not and amongsuccessful entrants than failures. Our results question claims that entrepreneurs areoverconfident and emphasize the need to understand the role of judgmental fallibility inproducing economic outcomes.

Is confidence in decisions related to feedback? Evidence-and lack of evidence-from random samples of real-world managerial behavior?

Confidence in decision making is an important dimension of managerialbehavior. However, what is the relation between confidence, on the onehand, and the fact of receiving or expecting to receive feedback ondecisions taken, on the other hand? To explore this and related issuesin the context of everyday decision making, use was made of the ESM(Experience Sampling Method) to sample decisions taken by undergraduatesand business executives. For several days, participants received 4 or 5SMS messages daily (on their mobile telephones) at random moments at whichpoint they completed brief questionnaires about their current decisionmaking activities. Issues considered here include differences between thetypes of decisions faced by the two groups, their structure, feedback(received and expected), and confidence in decisions taken as well as inthe validity of feedback. No relation was found between confidence indecisions and whether participants received or expected to receivefeedback on those decisions. In addition, although participants areclearly aware that feedback can provide both confirming and disconfirming evidence, their ability to specify appropriatefeedback is imperfect. Finally, difficulties experienced inusing the ESM are discussed as are possibilities for further researchusing this methodology.

Measuring and explaining farm inefficiency in a panel data set of mixed farms

This paper aims to estimate a translog stochastic frontier production function in the analysis of a panel of 150 mixed Catalan farms in the period 1989-1993, in order to attempt to measure and explain variation in technical inefficiency scores with a one-stage approach. The model uses gross value added as the output aggregate measure. Total employment, fixed capital, current assets, specific costs and overhead costs are introduced into the model as inputs. Stochasticfrontier estimates are compared with those obtained using a linear programming method using a two-stage approach. The specification of the translog stochastic frontier model appears as an appropriate representation of the data, technical change was rejected and the technical inefficiency effects were statistically significant. The mean technical efficiency in the period analyzed was estimated to be 64.0%. Farm inefficiency levels were found significantly at 5%level and positively correlated with the number of economic size units.