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Hypothesis Generation (hypothesis + generation)
Selected AbstractsA Note on the Interdependence between Hypothesis Generation and Information Search in Conducting Analytical Procedures,CONTEMPORARY ACCOUNTING RESEARCH, Issue 2 2003Stephen K. Asare Abstract This study examines the linkage among the initial hypothesis set, the information search, and decision performance in performing analytical procedures. We manipulated the quality of the initial hypothesis set and the quality of the information search to investigate the extent to which deficiencies (or benefits) in either process can be remedied (or negated) by the other phase. The hypothesis set manipulation entailed inheriting a correct hypothesis set, inheriting an incorrect hypothesis set, or generating a hypothesis set. The information search was manipulated by providing a balanced evidence set to auditors (i.e., evidence on a range of likely causes including the actual cause - analogous to a standard audit program) or asking them to conduct their own search. One hundred and two auditors participated in the study. The results show that auditors who inherit a correct hypothesis set and receive balanced evidence performed better than those who inherit a correct hypothesis set and did their own search, as well as those who inherited an incorrect hypothesis set and were provided a balanced evidence set. The former performance difference arose because auditors who conducted their own search were found to do repeated testing of non-errors and truncated their search. This suggests that having a correct hypothesis set does not ensure that a balanced testing strategy is employed, which, in turn, diminishes part of the presumed benefits of a correct hypothesis set. The latter performance difference was attributable to auditors' failure to generate new hypotheses when they received evidence about a hypothesis that was not in the current hypothesis set. This demonstrates that balanced evidence does not fully compensate for having an initial incorrect hypothesis set. These findings suggest the need for firm training and/or decision aids to facilitate both a balanced information search and an iterative hypothesis generation process. [source] Solving Inductive Reasoning Problems in Mathematics: Not-so-Trivial PursuitCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 2 2000Lisa A. Haverty This study investigated the cognitive processes involved in inductive reasoning. Sixteen undergraduates solved quadratic function,finding problems and provided concurrent verbal protocols. Three fundamental areas of inductive activity were identified: Data Gathering, Pattern Finding, and Hypothesis Generation. These activities are evident in three different strategies that they used to successfully find functions. In all three strategies, Pattern Finding played a critical role not previously identified in the literature. In the most common strategy, called the Pursuit strategy, participants created new quantities from x and y, detected patterns in these quantities, and expressed these patterns in terms of x. These expressions were then built into full hypotheses. The processes involved in this strategy are instantiated in an ACT-based model that simulates both successful and unsuccessful performance. The protocols and the model suggest that numerical knowledge is essential to the detection of patterns and, therefore, to higher-order problem solving. [source] Predictive toxicogenomics approaches reveal underlying molecular mechanisms of nongenotoxic carcinogenicityMOLECULAR CARCINOGENESIS, Issue 12 2006Alex Y. Nie Toxicogenomics technology defines toxicity gene expression signatures for early predictions and hypotheses generation for mechanistic studies, which are important approaches for evaluating toxicity of drug candidate compounds. A large gene expression database built using cDNA microarrays and liver samples treated with over one hundred paradigm compounds was mined to determine gene expression signatures for nongenotoxic carcinogens (NGTCs). Data were obtained from male rats treated for 24 h. Training/testing sets of 24 NGTCs and 28 noncarcinogens were used to select genes. A semiexhaustive, nonredundant gene selection algorithm yielded six genes (nuclear transport factor 2, NUTF2; progesterone receptor membrane component 1, Pgrmc1; liver uridine diphosphate glucuronyltransferase, phenobarbital-inducible form, UDPGTr2; metallothionein 1A, MT1A; suppressor of lin-12 homolog, Sel1h; and methionine adenosyltransferase 1, alpha, Mat1a), which identified NGTCs with 88.5% prediction accuracy estimated by cross-validation. This six genes signature set also predicted NGTCs with 84% accuracy when samples were hybridized to commercially available CodeLink oligo-based microarrays. To unveil molecular mechanisms of nongenotoxic carcinogenesis, 125 differentially expressed genes (P,<,0.01) were selected by Student's t -test. These genes appear biologically relevant, of 71 well-annotated genes from these 125 genes, 62 were overrepresented in five biochemical pathway networks (most linked to cancer), and all of these networks were linked by one gene, c - myc. Gene expression profiling at early time points accurately predicts NGTC potential of compounds, and the same data can be mined effectively for other toxicity signatures. Predictive genes confirm prior work and suggest pathways critical for early stages of carcinogenesis. © 2006 Wiley-Liss, Inc. [source] Altered gene expression in the brain and ovaries of zebrafish (Danio Rerio) exposed to the aromatase inhibitor fadrozole: Microarray analysis and hypothesis generation,,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2009Daniel L. Villeneuve Abstract As part of a research effort examining system-wide responses of the hypothalamic-pituitary-gonadal (HPG) axis in fish to endocrine-active chemicals (EACs) with different modes of action, zebrafish (Danio rerio) were exposed to 25 or 100 ,g/L of the aromatase inhibitor fadrozole for 24, 48, or 96 h. Global transcriptional response in brain and ovarian tissue of fish exposed to 25 ,g/L of fadrozole was compared to that in control fish using a commercially available, 22,000-gene oligonucleotide microarray. Transcripts altered in brain were functionally linked to differentiation, development, DNA replication, and cell cycle. Additionally, multiple genes associated with the one-carbon pool by folate pathway (KEGG 00670) were significantly up-regulated. Transcripts altered in ovary were functionally linked to cell-cell adhesion, extracellular matrix, vasculogenesis, and development. Promoter motif analysis identified GATA-binding factor 2, Ikaros 2, alcohol dehydrogenase gene regulator 1, myoblast-determining factor, and several heat shock factors as being associated with coexpressed gene clusters that were differentially expressed following exposure to fadrozole. Based on the transcriptional changes observed, it was hypothesized that fadrozole elicits neurodegenerative stress in brain tissue and that fish cope with this stress through proliferation of radial glial cells. Additionally, it was hypothesized that changes of gene expression in the ovary of fadrozole-exposed zebrafish reflect disruption of oocyte maturation and ovulation because of impaired vitellogenesis. These hypotheses and others derived from the microarray results provide a foundation for future studies aimed at understanding responses of the HPG axis to EACs and other chemical stressors. [source] The Impact of Generating Initial Hypothesis Sets of Different Sizes on the Quality of the Initial Set, and the Resulting Time Efficiency and Final Judgment AccuracyINTERNATIONAL JOURNAL OF AUDITING, Issue 1 2004Sudip Bhattacharjee This study examines the impact of generating initial hypothesis sets of different sizes on the quality of the hypotheses generated (i.e., the ability to consider both the direction and accounts that are over- or understated). We also examine the time efficiency, information search effectiveness, and the final judgment accuracy, conditional on the quality of the initial hypothesis set. Sixty auditors performed an analytical procedures task where they were asked to generate and test either a specific number of initial hypotheses (one, three, or six), or any number of hypotheses desired in order to uncover an error seeded in the financial statements. The results indicate that the three hypotheses group initially generated hypotheses of the highest quality and maintained the hypothesis quality after efficiently searching information and generating additional causes. The one hypothesis group improved the quality of their hypotheses only after generating and testing several causes. However, auditors who generated six hypotheses or any number desired (as in audit practice) considered hypotheses of lower quality in the initial set, and did not improve the hypotheses quality after going through the information search stage. These results suggest that the size of the initial hypothesis set can lead to differences in the gains that accrue from the hypothesis generation and information search stages of diagnostic decisions. [source] Design Considerations for Research on Analytical ProceduresINTERNATIONAL JOURNAL OF AUDITING, Issue 3 2001Stephen K. Asare This article discusses research design considerations for conducting behavioral research on auditors' performance of analytical procedures (APs). With the trend in practice towards increasing reliance on APs, it is essential that auditors are proficient in completing such tests. Therefore, research to understand and improve auditors' performance of APs is important. Once an unexpected fluctuation is identified, APs involve three phases: generation of plausible hypotheses (likely causes); gathering evidence to examine plausible hypotheses; and identification of the most likely cause followed by appropriate follow-up actions. Although prior research has focused on these phases in isolation, they are, in fact, interrelated. Important research design issues and trade-offs for each of the phases of APs are discussed. For instance, in examining hypothesis generation there are choices as to the amount and nature of case background information, number of ratios or accounts to explain; ex-post evaluation of the quality of the hypothesis set; and instructions on number of causes that account for the fluctuation. Significant considerations are identified for making informed decisions among design choices. [source] No decision-maker is an Island: integrating expert advice with information acquisitionJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 1 2006Gunnar E. Schrah Abstract The present research examined the social context of information acquisition. The main purpose was to examine how decision-makers' information acquisition processes changed when they were provided access to expert advice. Results indicated that all decision-makers opted to acquire advice; however, they typically did so only after completing over 75% of their own information search. Decision-makers agreed more with the advice as task complexity increased, but, in general, searched information in two stages,i.e., a pre-advice "hypothesis generation" stage and a post-advice "hypothesis testing" stage. To behave in an adaptive manner, decision-makers could have used expert advice either to increase their decision accuracy or to reduce their effort expenditure (or both); they chose the former. Implications and further extensions are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] The Quebec Overfeeding Study: a catalyst for new hypothesis generationOBESITY REVIEWS, Issue 1 2004Article first published online: 16 JAN 200 [source] Conceptual Models of Health Behavior: Research in the Emergency Care SettingsACADEMIC EMERGENCY MEDICINE, Issue 11 2009Edwin D. Boudreaux PhD Abstract This article provides recommendations for incorporating conceptual models of health behavior change into research conducted in emergency care settings. The authors drafted a set of preliminary recommendations, which were reviewed and discussed by a panel of experienced investigators attending the 2009 Academic Emergency Medicine consensus conference. The original recommendations were expanded and refined based on their input. This article reports the final recommendations. Three recommendations were made: 1) research conducted in emergency care settings that focuses on health behaviors should be grounded in formal conceptual models, 2) investigators should clearly operationalize their outcomes of interest, and 3) expected relations between theoretical constructs and outcomes should be made explicit prior to initiating a study. A priori hypothesis generation grounded in conceptual models of health behavior, followed by empirical validation of these hypotheses, is needed to improve preventive and public health,related interventions in emergency care settings. [source] Accommodating Surprise in Taxonomic Tasks: The Role of ExpertiseCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 1 2000Eugenio Alberdi This paper reports a psychological study of human categorization that looked at the procedures used by expert scientists when dealing with puzzling items. Five professional botanists were asked to specify a category from a set of positive and negative instances. The target category in the study was defined by a feature that was unusual, hence situations of uncertainty and puzzlement were generated. Subjects were asked to think aloud while solving the tasks, and their verbal reports were analyzed. A number of problem solving strategies were identified, and subsequently integrated in a model of knowledge-guided inductive categorization. Our model proposes that expert knowledge influences the subjects' reasoning in more complex ways than suggested by earlier investigations of scientific reasoning. As in previous studies, domain knowledge influenced our subjects' hypothesis generation and testing; but, additionally, it played a central role when subjects revised their hypotheses. [source] | |||||||||||||