Confirmatory and diagnosing strategies in social information gathering.

In 3 experiments, 342 Ss (including 199 undergraduates) were asked to test the hypothesis that another person possesses a certain personality trait by selecting sources of behavioral evidence. The 2 main informational properties on which these sources of evidence varied were (a) the probability of the evidence under the hypothesized trait, from highly probable to highly improbable, and (b) the diagnosticity of the evidence. Results show that diagnosticity was the major determinant of the information-gathering preferences. There was very little evidence for a confirmatory strategy wherein evidence probable under the hypothesized trait was preferred to evidence improbable under this trait. In fact, improbable evidence was preferred when it was more diagnostic than probable evidence. It is concluded that the confirmatory strategy did not reduce the diagnostic power of the information assembled. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A simple linear heuristic for the service constrained random yield problem

We consider the problem of setting order quantities for purchased components subject to uncertainty in the delivery amounts. Assuming the periodic production volumes (demands)to be known and constant, we model this as a random yield problem with the objective of minimizing average inventory cost subject to a service level constraint over the infinite horizon. We first demonstrate that under conditions of random yield, conventional definitions of service can be inappropriate. Then we refine the definition of service for random yield cases and use this to formulate an optimization model. Exact solution of this model proves to be computationally impractical and, as we show, the common heuristic of inflating demands by a constant proportion is not robustly accurate. Therefore, we develop a new heuristic, which we term the linear inflation policy, that specifies a linear function for the inflation factors. Numerical tests indicate that this heuristic can substantially outperform the traditional constant inflation policy and works well relative to a lower bound on the optimal solution on a range of examples.     

Priming addition facts with semantic relations.

Results from 2 relational-priming experiments suggest the existence of an automatic analogical coordination between semantic and arithmetic relations. Word pairs denoting object sets served as primes in a task that elicits "obligatory" activation of addition facts (5 + 3 activates 8; J. LeFevre, J. Bisanz, & L. Mrkonjic, 1988). Semantic relations between the priming words were either aligned or misaligned with the structure of addition (M. Bassok, V. M. Chase, & S. A. Martin, 1998). Obligatory activation of addition facts occurred when the digits were primed by categorically related words (tulips-daisies), which are aligned with addition, but did not occur when the digits were primed by unrelated words (hens-radios, Experiment 1) or by functionally related words (records-songs, Experiment 2), which are misaligned with addition. These findings lend support to the viability of automatic analogical priming (B. A. Spellman, K. J. Holyoak, & R. G. Morrison, 2001) and highlight the relevance of arithmetic applications to theoretical accounts of mental arithmetic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Approximations for multiproduct contracts with stochastic demands and business volume discounts: single supplier case

In this paper we analyze contracts for multiple products when the supplier offers business volume discounts. The contract takes the form of price discounts for total minimum dollar volume commitments over the horizon with flexibility to adjust the total purchases upwards by a fixed percentage about this minimum commitment. The optimal policy could be complex since it involves the solution of a constrained multi-period multi-product dynamic program. We suggest approximations that give us an upper bound. To develop this upper bound, we present the optimal policy for a similar contract for a single product problem. We then develop a lower bound for the multiproduct problem and show, numerically, that the gap is small. Given the approximations standard single period resource allocation algorithms can be used to solve the problem. The resulting solution methodology is fast and permits evaluation of various what-if scenarios.     

Object-based representations: Transfer between cases of continuous and discrete models of change.

The authors examined why similarities and differences between the objects of analogous problems affect transfer. They present results showing that object attributes affect transfer by affecting the way in which people represent problem structures (e.g., speed changes continuously and monetary investments discretely). Participants learned to solve problems involving either constant change in speed or in investment. They were then tested for transfer to problems that were matched on a variety of object attributes but involved entities known to be changing either continuously or discretely (e.g., melting ice vs. ice delivered to a restaurant). Although the manner of change was never specified as a constraint for solving the training problems, transfer in the continuous-to-discrete direction was rare and involved laborious mappings, whereas transfer in the discrete-to-continuous direction was frequent and straightforward. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Interdomain transfer between isomorphic topics in algebra and physics": Correction to Bassok and Holyoak (1989).

Reports an error in "Interdomain transfer between isomorphic topics in algebra and physics" by Miriam Bassok and Keith J. Holyoak (Journal of Experimental Psychology: Learning, Memory, and Cognition, 1989[Jan], Vol 15[1], 153-166). On page 157, parts of two sentences in the Results and Discussion section were omitted. The corrected sentences are provided in the erratum. (The following abstract of the original article appeared in record 1989-17879-001.) Three experiments examined transfer between 2 isomorphic subdomains of algebra and physics. The two areas were arithmetic-progression problems in algebra and constant-acceleration problems in physics. High school and college students who had learned one of these subtopics were presented with word problems that used either content from the domain they had originally studied or content based on the unfamiliar but analogous domain. Ss who had learned arithmetic progressions were very likely to spontaneously recognize that physics problems involving velocity and distance can be addressed using the same equations. Analysis of problem-solving protocols revealed that the recognition was immediate and that the solutions were a straightforward application of the algebraic method. Such recognition occurred even when the algebraic procedures were taught using example word problems all of which were drawn from a single content area (e.g., "money" problems). In contrast, Ss who had learned the physics topic almost never exhibited any detectable transfer to the isomorphic algebra problems. The results were interpreted in terms of content-free vs content-specific applicability conditions for mathematical procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transfer of domain-specific problem-solving procedures.

Two experiments examined transfer of mathematical problem-solving procedures learned in content-rich quantitative domains (e.g., physics, finance) to isomorphic algebra word problems dealing with other contents. In spite of content-specific embedding, many high school and college students exhibited spontaneous transfer when the variables in the learned and in the transfer problems represented similar types of quantities (e.g., speed and typing rate). Spontaneous transfer to structurally isomorphic problems with variables representing different types of quantities (e.g., speed and salary) was blocked. Protocol analyses showed that for matching quantities, transfer solutions were straightforward applications of the learned methods, whereas transfer to problems with nonmatching quantities demanded a hint for retrieval followed by an effortful process of abstraction and analogical mapping. The results suggest a complex interrelation between content and structure: Many features of the embedding content may be "screened out" as irrelevant, but content features used for interpretation of variables (e.g., intensive vs. extensive) may affect both access and use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interdomain transfer between isomorphic topics in algebra and physics.

[Correction Notice: An erratum for this article was reported in Vol 15(5) of Journal of Experimental Psychology: Learning, Memory, and Cognition (see record 2008-10689-001). On page 157, parts of two sentences in the Results and Discussion section were omitted. The corrected sentences are provided in the erratum.] Three experiments examined transfer between 2 isomorphic subdomains of algebra and physics. The two areas were arithmetic-progression problems in algebra and constant-acceleration problems in physics. High school and college students who had learned one of these subtopics were presented with word problems that used either content from the domain they had originally studied or content based on the unfamiliar but analogous domain. Ss who had learned arithmetic progressions were very likely to spontaneously recognize that physics problems involving velocity and distance can be addressed using the same equations. Analysis of problem-solving protocols revealed that the recognition was immediate and that the solutions were a straightforward application of the algebraic method. Such recognition occurred even when the algebraic procedures were taught using example word problems all of which were drawn from a single content area (e.g., "money" problems). In contrast, Ss who had learned the physics topic almost never exhibited any detectable transfer to the isomorphic algebra problems. The results were interpreted in terms of content-free vs content-specific applicability conditions for mathematical procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)