The role of ecological validity in hazard perception assessment

Hazard perception is one of the few quantifiable components of driving competency that can explain the high crash risk of novice drivers (see Horswill & McKenna, 2004). Some studies focused on investigating the stimulus part of hazard perception items by comparing several design features of the displayed traffic scenarios (e.g. Malone et al., 2012; Scialfa et al., 2013). Other empirical studies have been conducted to address the reaction part of hazard perception items (e.g. Vlakveld, 2014). Among others, existing hazard perception tests differ with respect to the ecological validity – the similarity to real-world demands – of the task that has to be completed by the participants (simple reaction, hazard localization, simulated driving, etc.). Based on the findings of general expertise research (see Glaser & Chi, 1988), the hypothesis of the present experiment was that an increased ecological validity of a hazard perception task has a positive effect on the magnitude of performance differences between more and less experienced drivers. 104 learner drivers and 51 experienced drivers were randomly assigned either to a less ecological valid version (multiple choice task) or a higher ecological valid version (reaction task) of a hazard perception test. In both conditions, the same 20 animated hazardous or non-hazardous traffic scenarios were presented. Overall, the experienced drivers outperformed the learner drivers. Principally, both of the applied versions of the test provided a criterion valid measure of driving expertise. However, increasing the ecological validity of the test by using a reaction task was especially beneficial for certain types of scenarios, leading to higher expertise-related differences. In addition, the reaction task provides response time measure as a further valid performance indicator. This allows the identification of those participants who are indeed able to detect a hazard in a certain scenario, but still have deficits in response time, compared to more experienced drivers. According to the present study, it is recommended to choose the reaction task over the multiple choice task to test hazard perception. Whether a further increase in ecological validity of the task would be useful, should be tested empirically in future research.     

Improving an optimization‐based framework for sensitivity analysis in multi‐criteria decision‐making

The framework for sensitivity analysis in discrete multi‐criteria decision analysis developed by Rios Insua and French allows simultaneous variation of all parameters and applies to many paradigms for decision analysis. However, its computational load may inhibit use, particularly in the context of a decision conference where results are required in near real time. In order to improve on the current algorithm and its implementation, we investigate, on the one hand, an opportunistic approach aimed at reducing the number of optimization problems solved in the original framework and, on the other, an alternative framework based on distance analysis. Computational results on linear and bilinear models are reported. Copyright © 2001 John Wiley & Sons, Ltd.     

Assessing risky public investments with MUSTARD

This paper presents a practical implementation of multicriteria methodologies based on the UTA model by Jacquet‐Lagrèze and Siskos and Quasi‐UTA model by Beuthe and Scannella, which are specified with a non‐linear, but piecewise linear, additive utility function. In contrast with the general UTA model, the Quasi‐UTA specification structures the partial utilities as recursive exponential functions of only one curvature parameter. This allows for a reduction of the quantity of information necessary to build the utility function. The software MUSTARD implements different variants of these models. Firstly, it offers the basic deterministic UTA model of disaggregation, but also its first programmed stochastic version. In both cases, the software proceeds stepwise and interactively helping the decision maker to formulate the problem and state preferences between projects; in the stochastic case, the decision maker is even helped to build the criteria distributions. The Quasi‐UTA specification can be introduced in this disaggregation model. Secondly, the software offers an aggregation model whereby the Quasi‐UTA partial utility functions are built separately through specific questioning processes. The questions relating to deterministic criteria are of the ‘direct rating type’, while those of the stochastic criteria are either of the ‘variable probability’ or the ‘variable outcome’ type. The criteria weights can be assessed by the ‘swing weight’ method or by a UTA‐II side‐program. As an example as well as a test of the Quasi‐UTA aggregation approach, the paper presents its application to a real problem of selecting road investment projects in Belgium. Several experts and civil servants were interviewed, and their individual utility functions derived. The projects are ranked according to their rate of return, which is computed on the basis of the projects certain equivalent money value. Copyright © 2002 John Wiley & Sons, Ltd.     

An evaluation of multi‐criteria methods in integrated assessment of climate policy

Those who conduct integrated assessments (IAs) are aware of the need to explicitly consider multiple criteria and uncertainties when evaluating policies for preventing global warming. MCDM methods are potentially useful for understanding tradeoffs and evaluating risks associated with climate policy alternatives. A difficulty facing potential MCDM users is the wide range of different techniques that have been proposed, each with distinct advantages. Methods differ in terms of validity, ease of use, and appropriateness to the problem. Alternative methods also can yield strikingly different rankings of alternatives. A workshop was held in which climate change experts and policy makers evaluated the usefulness of MCDM for IA. Participants applied several methods in the context of a hypothetical greenhouse gas policy decision. Methods compared include value and utility functions, goal programming, ELECTRE, fuzzy sets, stochastic dominance, min max regret, and several weight selection methods. Ranges, rather than point estimates, were provided for some questions to incorporate imprecision regarding weights. Additionally, several visualization methods for both deterministic and uncertain cases were used and evaluated. Analysis of method results and participant feedback through questionnaires and discussion provide the basis for conclusions regarding the use of MCDM methods for climate change policy and IA analyses. Hypotheses are examined concerning predictive and convergent validity of methods, existence of splitting bias among experts, perceived ability of methods to aid decision‐making, and whether expressing imprecision can change ranking results. Because participants gained from viewing a problem from several perspectives and results from different methods often significantly differed, it appears worthwhile to apply several MCDM methods to increase user confidence and insight. The participants themselves recommended such multimethod approaches for policymaking. Yet they preferred the freedom of unaided decision‐making most of all, challenging the MCDM community to create transparent methods that permit maximum user control. Copyright © 2002 John Wiley & Sons, Ltd.     

Attribute‐based differentiation of alternatives

An intermediate step is introduced to the dialogue decision process for decision analysis. Alternatives are refined after they have been generated within a strategy table but before they are subject to more detailed evaluation. Two or more judges create a subjective mapping from alternatives to attributes that will later be mapped to criteria. In strategy tables, each of the alternative strategies consists of a coherent set of choices made across several decisions that are to be coordinated. These strategic alternatives are modified so as to increase their differentiation in the attribute space, rather than in the decision space alone. When criteria weights are unknown, the best alternative from the modified set may be superior to the best alternative from the original set. Furthermore, analysis of the resulting alternatives may yield a better mapping of the value response surface for the action space, in the sense that this mapping leads to eventual construction of a higher value alternative. Results are reported for a consulting engagement incorporating the proposed step. Copyright © 2003 John Wiley & Sons, Ltd.     

影响儿童至老年人“位置法”记忆训练效果的因素探析

１１８名儿童、少年、青年、中年和老年被试参加＂位置法＂记忆训练,在训练前后对被试进行了一些认知功能的测查,以探讨被试的年龄及认知能力诸因素对记忆训练效果的影响及其预测性。结果表明：①训练前字词和图形记忆成绩、＂数字符号＂测验成绩与训练后记忆成绩相关极其显著,＂词汇＂测验成绩和想象力与训练后记忆成绩的相关也达到显著性水平;②年龄与训练后记忆效果的关系是非线性的;③除＂词汇＂成绩外,各项认知成绩均可预测训练后字词记忆成绩,训练后的图形记忆迁移效果可由＂数字符号＂测验成绩预测。     

The effects of different mastery criteria on the skill maintenance of children with developmental disabilities

The acquisition of skills by individuals with developmental disabilities typically includes the attainment of a certain mastery criterion. We conducted a survey of practitioners who indicated the most commonly used mastery criterion as 80% accuracy across three consecutive sessions. Based on these results, we conducted a series of three experiments to evaluate the relation between mastery criterion and subsequent skill maintenance with 4 individuals with various developmental disabilities. Results suggest that 80% accuracy across three consecutive sessions may be insufficient for producing maintenance in some cases.