Identification of the 1PL Model with Guessing Parameter: Parametric and Semi-parametric Results

In this paper, we study the identification of a particular case of the 3PL model, namely when the discrimination parameters are all constant and equal to 1. We term this model, 1PL-G model. The identification analysis is performed under three different specifications. The first specification considers the abilities as unknown parameters. It is proved that the item parameters and the abilities are identified if a difficulty parameter and a guessing parameter are fixed at zero. The second specification assumes that the abilities are mutually independent and identically distributed according to a distribution known up to the scale parameter. It is shown that the item parameters and the scale parameter are identified if a guessing parameter is fixed at zero. The third specification corresponds to a semi-parametric 1PL-G model, where the distribution G generating the abilities is a parameter of interest. It is not only shown that, after fixing a difficulty parameter and a guessing parameter at zero, the item parameters are identified, but also that under those restrictions the distribution G is not identified. It is finally shown that, after introducing two identification restrictions, either on the distribution G or on the item parameters, the distribution G and the item parameters are identified provided an infinite quantity of items is available.     

Examining the Effects of Social Bonds and Shame on Drug Recovery within an On-Line Support Community

Past research has demonstrated the utility of on-line support groups for individuals to form relationships and make connections. Additionally, some on-line communities have expanded to provide various types of support, particularly for deviant behavior. These virtual communities may be particularly indispensable to individuals who, out of fear of condemnation, are reluctant to seek traditional forms of social support. For purposes of this study, we examined how members of a substance abuse recovery on-line support group expressed feelings pertaining to their own substance abuse, as well as their processes of attempted or successful recovery. Using an inductive approach for our preliminary analysis, we first assessed which theories were most prevalent throughout the writers’ journals. We then used these theories, both Hirschi’s theory of social control and Braithwaite’s theory of reintegrative shaming, as frameworks to explore the differences between those who were in recovery and those who were still using.     

Semantic Processing of Foveally and Parafoveally Presented Words in a Lexical Decision Task

Using a lexical decision task in which two primes appeared simultaneously in the visual field for 150 msec followed by a target word, two experiments examined semantic priming from attended and unattended primes as a function of both the separation between the primes in the visual field and the prime-target stimulus-onset asynchrony (SOA). In the first experiment significant priming effects were found for both the attended and unattended prime words, though the effect was much greater for the attended words. In addition, and also for both attention conditions, priming showed a tendency to increase with increasing eccentricity (2.3°, 3.3°, and 4.3°) between the prime words in the visual field at the long (550 and 850 msec) but not at the short (250 msec) prime-target SOA. In the second experiment the prime stimuli were either two words (W-W) or one word and five Xs (W-X). We manipulated the degree of eccentricity (2° and 3.6°) between the prime stimuli and used a prime-target SOA of 850 msec. Again significant priming was found for both the attended and unattended words but only the W-W condition showed a decrement in priming as a function of the separation between the primes; this decrement came to produce negative priming for the unattended word at the narrow (2°) separation. These results are discussed in relation to the semantic processing of parafoveal words and the inhibitory effects of focused attention.     

Ethics in Finance Research: Recommendations from an Academic Experts Delphi Panel

This paper examines the flow of thoughts on ethics in finance both from academic experts and from published contributions that constitute an alternative view of the financial field from an ethical point of view. A Delphi method was used to achieve consensus about the perceptions and opinions academic experts hold about ethics in financial matters and in the research agenda. This approach permits the early detection of emerging lines, narrowing the research line and shortening subject selection time. An active research map of researchers, countries and lines of investigation was drawn up, and recommendations made of areas that could be highlighted or moderated.     

The International Affective Digitized Sounds (IADS): Spanish norms

The International Affective Digitized Sounds (IADS): Spanish Norms. The Spanish norms for the International Affective Digitized Sounds (IADS) are reported. The IADS is a standardized set of 110 digitalized sounds which are both reliable and valid for the experimental study of emotional processes. The construction of the IADS is based on Peter J. Lang's dimensional model of emotions. Participants were 1.716 university students (1.136 women) who assessed the sounds using the three scales of the Self-Assessment Manikin: affective valence, arousal, and dominance. The results show a distribution of the sounds, within the bidimensional plot defined by valence and arousal, similar to the North-American student population with a typical boomerang shape. No significant differences were found when comparing men and women nor when comparing the Spanish and North-American samples in the total set of sounds. The results are discussed in relation to the International Affective Picture System (IAPS). The norms for each of the 110 sounds are presented in an annexed table.     

Effects of extinction in multiple contexts on the renewal of associative tolerance to ethanol

The Pavlovian analysis of drug tolerance describes how the contexts of drug administration participate in the elicitation of compensatory conditioned responses that are, at least partly, responsible for tolerance. Findings indicate that if an association is acquired in one context and extinguished in another one, when exposing the subjects to the acquisition context, renewal of the conditioned response will take place. Ambiguous evidence exists about whether or not this effect diminishes when extinguishing the association in multiple contexts. This investigation evaluates the existence of the phenomenon of renewal of tolerance to ethanol, and whether it diminishes by the extinction in multiple contexts. Evidence of renewal of tolerance to ethanol in rats was found, but no diminution was observed when extinguishing in multiple contexts.     

Implicit sequence learning in a search task

This study investigated the effects of selection demands on implicit sequence learning. Participants in a search condition looked for a target among seven distractors and responded on the target identity. The responses followed a deterministic sequence, and sequence learning was compared to that found in two control conditions in which the targets were presented alone, either at a central location or over a series of unpredictable locations. Sequence learning was obtained in all conditions, and it was equivalent for the two variable location conditions, regardless of the perceptual demands. Larger effects of learning were observed in the central location, both on the indirect measures and on the measures taken from a cued-generation task. The expression of learning decreased selectively in this condition when the sequence validity was reduced over a test block. These results are consistent with the claims that implicit and explicit learning are mixed in this central condition and that implicit learning is not affected by selection difficulty.     

Inferential basing and mental models

In this paper, I flesh out an account of the inferential basing relation using a theory about how humans reason: the mental models theory. I critically assess some of the notions that are used by that theory to account for inferential phenomena. To the extent that the mental models theory is well confirmed, that account of basing would be motivated on empirical grounds. This work illustrates how epistemologists could offer explications of the basing relation which are more detailed and less empirically risky.