ACCURACY AND ERROR IN ELECTORAL FORECASTS: THE CASE OF MEXICO

Forecast errors in preelectoral polls are common. Since theNicaraguan Election in 1990, a common assumption is that wheredemocratic practices are not equal to those of the developedcountries (authoritarian, in transition, etc.), the errors inpredicting electoral outcomes with the help of pre-electoralpolls result mostly from contextual effects related to the authoritariannature of the political systems. Forecast errors in developeddemocracies have been explained by flaws in sampling (GreatBritain), last minute changes in preferences (Spain, UnitedStates, and France) and a social desirability bias in the UnitedStates. The intention of this paper is to show that in Mexicoboth the accuracy and the sources of error in predicting electoralresults are very similar to those confronted by pollsters elsewhere:mostly sampling and allocation of nonrespondents and those whoare undecided. An extensive data set of pre-electoral pollsconducted in Mexico shows an average error in the order of 3–5percentage points. Some of this error could be related to sociallydesirable answers derived from contextual effects, but thiseffect is small and must not be generalized.     

Anticipatory strategies of team-handball goalkeepers

Abstract

This study seeks to discover whether handball goalkeepers employ a general anticipatory strategy when facing long distance throws and the effect of uncertainty on these strategies. Seven goalkeepers and four throwers took part. We used a force platform to analyse the goalkeeper's movements on the basis of reaction forces and two video cameras synchronised at 500 Hz to film the throw using 3D video techniques. The goalkeepers initiated their movement towards the side of the throw 193 ± 67 ms before the release of the ball and when the uncertainty was reduced the time increased to 349 ± 71 ms. The kinematics analysis of their centre of mass indicated that there was an anticipatory strategy of movement with certain modifications when there was greater uncertainty. All the average scores referring to velocity and lateral movement of the goalkeeper's centre of mass are significantly greater than those recorded for the experimental situation with bigger uncertainty. The methodology used has enabled us to tackle the study of anticipation from an analysis of the movement used by goalkeepers to save the ball.     

What do I want to feel? Emotion goals in childhood,adolescence, and adulthood

Beliefs about emotion utility can influence context-sensitive emotion goals (i.e., desired emotional responses). Although key for emotion regulation, emotion goals have been overlooked in children and adolescents. In 2018–2019 results of Studies 1 and 2 showed that children (N = 192, M_age = 8.65, 47% girls, 96% White) were less motivated by and found anger less useful in confrontation than adolescents (N = 192, M_age = 12.96, 50% girls, 93% White) and adults (N = 195, M_age = 29.82, 51% women, 96% White). The link between emotion goals and beliefs about emotion utility was weaker in children. In 2021, Study 3 (N = 60, 8-year-olds, 47% girls, 90% White) ruled out expectations as a possible explanation for the previous findings. Context-sensitive utility of emotions may be acquired during development.     

An analysis of two styles of arm action in the vertical countermovement jump

The aim of this study was to determine the effect of two arm swing techniques, the simultaneous arm swing and the early arm swing, on vertical countermovement jump performance and on the contribution of the arms to vertical movement at the centre of mass (CM) during the propulsion phase. Participants were 28 athletes practicing sports in which the vertical jump constitutes a basic ability. Ground reaction forces were recorded by a force platform and the sagittal plane motion was recorded by a video camera. Although at take-off the vertical velocity (2.7 ± 0.2 m/s for simultaneous technique vs. 2.8 ± 0.2 m/s for early technique; p = 0.040) and position (1.18 ± 0.06 m for simultaneous vs. 1.17 ± 0.05 m for early; p = 0.033) of the CM were significantly different, no difference was observed in jump height (1.56 ± 0.01 m in both techniques). The arm action differed during the initial and final propulsion phases in both styles but the accumulated vertical contribution was similar. The practical implication in sports is that the use of the arm-swing technique to reach the maximum jump height should be determined by tactical demands instead of the technical execution of the arms.     

A linear optimization approach to the combined production planning model

Two fundamental processes usually arise in the production planning of many industries. The first one consists of deciding how many final products of each type have to be produced in each period of a planning horizon, the well-known lot sizing problem. The other process consists of cutting raw materials in stock in order to produce smaller parts used in the assembly of final products, the well-studied cutting stock problem. In this paper the decision variables of these two problems are dependent of each other in order to obtain a global optimum solution. Setups that are typically present in lot sizing problems are relaxed together with integer frequencies of cutting patterns in the cutting problem. Therefore, a large scale linear optimizations problem arises, which is exactly solved by a column generated technique. It is worth noting that this new combined problem still takes the trade-off between storage costs (for final products and the parts) and trim losses (in the cutting process). We present some sets of computational tests, analyzed over three different scenarios. These results show that, by combining the problems and using an exact method, it is possible to obtain significant gains when compared to the usual industrial practice, which solve them in sequence.     

What We Talk About When We Talk About Nepantla: Gloria Anzaldúa and the Queer Fruit of Aztec Philosophy

A particular twenty-first-century understanding of the Aztec concept nepantla, one which has recently taken hold in critical education thanks to the writings of Gloria Anzaldúa, does not accurately reflect traditional Aztec history and philosophy. This essay reveals why this is the case, demonstrating in detail the meaning of nepantla within the broader Aztec ontology. It then asks education researchers and practitioners to instead use the theoretical framework of malinalli, the Aztec philosophical concept which best aligns with transformative social justice goals.     

The impact of the French policy mix on business R&D: How geography matters

Based on a spatial extension of an R&D investment model, this paper measures the macroeconomic impact of the French R&D policy mix on business R&D using regional data. Our measure takes into account not only the direct effect of policies but also indirect effects generated by the existence of spatial interaction between regions. Using a unique database containing information on the levels of various R&D policy instruments received by firms in French NUTS3 regions over the period 2001–2011, our estimates of a spatial Durbin model with structural breaks and fixed effects reveal the existence of a negative spatial dependence among R&D investments in regions. In this context, while a-spatial estimates would conclude that all instruments have a crowding-in effect, we show that national subsidies are the only instrument that is able to generate significant crowding-in effects. On the contrary, it seems that the design, size and spatial allocation of funds from the other instruments (tax credits, local subsidies, European subsidies) lead them to act (in the French context) as beggar-thy-neighbor policies.     

A methodological approach for object-relational database design using UML

The most common way of designing databases is by means of a conceptual model, such as E/R, without taking into account other views of the system. New object-oriented design languages, such as UML (Unified Modelling Language), allow the whole system, including the database schema, to be modelled in a uniform way. Moreover, as UML is an extendable language, it allows for any necessary introduction of new stereotypes for specific applications. Proposals exist to extend UML with stereotypes for database design but, unfortunately, they are focused on relational databases. However, new applications require complex objects to be represented in complex relationships, object-relational databases being more appropriate for these requirements. The framework of this paper is an Object-Relational Database Design Methodology, which defines new UML stereotypes for Object-Relational Database Design and proposes some guidelines to translate a UML conceptual schema into an object-relational schema. The guidelines are based on the SQL: 1999 object-relational model and on Oracle8i as a product example.Received: 22 January 2002, Revised: 10 June 2002, This paper is a revised and extended version of Extending UML for Object-Relational Database Design, presented in the UML2001 conference [17].