Problem-Focused Incremental Elicitation of Multi-Attribute Utility Models

Decision theory has become widely accepted in the AI community as a useful framework for planning and decision making. Applying the framework typically requires elicitation of some form of probability and utility information. While much work in AI has focused on providing representations and tools for elicitation of probabilities, relatively little work has addressed the elicitation of utility models. This imbalance is not particularly justified considering that probability models are relatively stable across problem instances, while utility models may be different for each instance. Spending large amounts of time on elicitation can be undesirable for interactive systems used in low-stakes decision making and in time-critical decision making. In this paper we investigate the issues of reasoning with incomplete utility models. We identify patterns of problem instances where plans can be proved to be suboptimal if the (unknown) utility function satisfies certain conditions. We present an..

PREFERENCES: OPTIMIZATION, IMPORTANCE LEARNING AND STRATEGIC BEHAVIORS

Preferences are fundamental to decision making and play an important role in artificial intelligence. Our research focuses on three group of problems based on the preference formalism Answer Set Optimization (ASO): preference aggregation problems such as computing optimal (near optimal) solutions, strategic behaviors in preference representation, and learning ranks (weights) for preferences. In the first group of problems, of interest are optimal outcomes, that is, outcomes that are optimal with respect to the preorder defined by the preference rules. In this work, we consider computational problems concerning optimal outcomes. We propose, implement and study methods to compute an optimal outcome; to compute another optimal outcome once the first one is found; to compute an optimal outcome that is similar to (or, dissimilar from) a given candidate outcome; and to compute a set of optimal answer sets each significantly different from the others. For the decision version of several of these problems we establish their computational complexity. For the second topic, the strategic behaviors such as manipulation and bribery have received much attention from the social choice community. We study these concepts for preference formalisms that identify a set of optimal outcomes rather than a single winning outcome, the case common to social choice. Such preference formalisms are of interest in the context of combinatorial domains, where preference representations are only approximations to true preferences, and seeking a single optimal outcome runs a risk of missing the one which is optimal with respect to the actual preferences. In this work, we assume that preferences may be ranked (differ in importance), and we use the Pareto principle adjusted to the case of ranked preferences as the preference aggregation rule. For two important classes of preferences, representing the extreme ends of the spectrum, we provide characterizations of situations when manipulation and bribery is possible, and establish the complexity of the problem to decide that. Finally, we study the problem of learning the importance of individual preferences in preference profiles aggregated by the ranked Pareto rule or positional scoring rules. We provide a polynomial-time algorithm that finds a ranking of preferences such that the ranked profile correctly decided all the examples, whenever such a ranking exists. We also show that the problem to learn a ranking maximizing the number of correctly decided examples is NP-hard. We obtain similar results for the case of weighted profiles

The role of culture in organisational and individual personnel selection decisions

The present consensus in the literature is that the traditional personnel selection paradigm is flawed and as a consequence, it has not readily been adopted into practice (Cascio & Aguinis, 2oo8). This disparity between research and practice has particularly been attributed to researchers' lack of awareness of the complex variables impacting organisational decision-making processes (Herriot & Anderson; 1997; Hodgkinson & Payne, 1998); the conceptualisation of scientific selection along a continuum based strictly on criterion validity indices (Hough & Oswald 2000; Borman, Hanson & Hedge, 1997) and a lack of clarity on the role of culture in selection research (Ryan, McFarland, Baron & Page, 1999; Moscoso & Salgado, 2004). In an attempt to identify the impact of these variables on personnel selection decisions, this thesis examines the landscape of what is generally viewed as scientific personnel selection by taking the discussion to a setting that is atypical of those normally represented in the selection research literature. The current scheme of research utilises samples from Jamaica to examine the role of culture in individual and organisational selection decisions. In so doing, studies throughout this thesis aim to challenge the assumption of universality espoused by the traditional psychometric paradigm in the measurement and understanding of personnel selection outcomes. Through a series of 6 studies quantitative, qualitative and experimental methods were adopted to determine the influence of cultural, internal and external factors on organisational decisions to utilise criterion-based selection techniques, applicant's decisions to pursue a job and selector decisions in a simulated managerial task. Findings revealed: a) Jamaica's colonial history, workermanager relationships and worker expectations influenced perceived personnel challenges, selection decisions and the likelihood of Jamaican organisations using criterion-based selection techniques; b) the cultural history necessitated a fit-based approached to selection and preference for techniques such as structured interviews, references and application forms; c) as represented by a multidimensional perceptual map, factors influencing Jamaican selection decisions are most similar to countries characterised by moderate power distance and masculinity indices (Australia and Canada) and most divergent to cultures characterised by extremely low individualism, high power distances and high long-term orientation (Taiwan and China); d) job and organisational factors influencing applicants' decisions to apply varied across cultures and applicant performing ability. Compared to UK graduates, higher-performing Jamaican applicants were more confident when applying to jobs emphasising performance although they preferred applying to jobs emphasising fit; e) for higher-performing Jamaican applicants, overall perceptions of structured interviews mediated the attractiveness of pay in their decision to pursue a job; f) framing and information order may mediate the process and outcomes of decisions rather than act as predictors of choices in and of themselves; and g) Jamaican selectors make attributions about a candidate's suitability based on perceptions of both functional and psychosocial consequences. Fit-based factors are given priority as fit with the organisation and team is cognitively weighted as better indicators of effective performance. Findings from all six studies emphasise the role of culture in individual and organisational personnel selection decisions and indicate 'scientific' personnel selection is more fit-based and culturally determined than previously suggested. It is therefore proposed that the dominant paradigm of personnel selection be reconceptualised from a psychometric emphasis to an attitudinal-cognitivebehavioural theoretical perspective which takes into account the impact of cultural and social variables on selection decisions. The implications of this alternate approach are discussed in relation to organisational, selector and applicant selection decisions and tackling future selection research agenda