Farm-related information use and users: A discussion of some European videotex experiences

Current discussions on the utilization of information technologies for agriculture, place emphasis on the collection and processing of information on the farm, through the introduction and use of computers as management support in process control and database management. However, because of farm management's dependency on outside information support for the production control and market engagement, the communication of information and the improvement of its efficiency is of similar, if not greater, importance. This article, therefore, places its main focus on the communication aspect. It provides a classification for “on-farm” communication patterns and highlights, using this classification, a number of European experiences with videotex applications in agriculture. It argues that new information technologies may open the way for new approaches to farm-related communication, and thus for a major change in farm management practices. For this progression to occur, its development and application should base itself upon the basic communication patterns that have evolved in practice, and reflect the actual use of information in agriculture. Mark Wilkinson is a cereal grower. He is editor of the Irish Farmers Association's closed user group, which was established on Agriline, a Videotex system.     

Diffusion of novel foraging behaviour in Amazon parrots through social learning

While social learning has been demonstrated in species across many taxa, the role it plays in everyday foraging decisions is not well understood. Investigating social learning during foraging could shed light on the emergence of cultural variation in different groups. We used an open diffusion experiment to examine the spread of a novel foraging technique in captive Amazon parrots. Three groups were tested using a two-action foraging box, including experimental groups exposed to demonstrators using different techniques and control birds. We also examined the influence of agonistic and pilfering behaviour on task acquisition. We found evidence of social learning: more experimental birds than control birds interacted with and opened the box. The birds were, however, no more likely to use the demonstrated technique than the non-demonstrated one, making local or stimulus enhancement the most likely mechanism. Exhibiting aggression was positively correlated with box opening, whilst receiving aggression did not reduce motivation to engage with the box, indicating that willingness to defend access to the box was important in task acquisition. Pilfering food and success in opening the box were also positively correlated; however, having food pilfered did not affect victims’ motivation to interact with the box. In a group context, pilfering may promote learning of new foraging opportunities. Although previous studies have demonstrated that psittacines are capable of imitation, in this naturalistic set-up there was no evidence that parrots copied the demonstrated opening technique. Foraging behaviour in wild populations of Amazons could therefore be facilitated by low-fidelity social learning mechanisms.     

Contextualization of Survey Data: What Do We Gain and Does It Matter?

Survey research designs that integrate contextual data have become more prevalent in recent decades, presumably to enable a more refined focus on the person as the unit of analysis and a greater emphasis on interindividual differences due to social forces and contextual conditions. This article reviews varied approaches to contextualizing survey data and examines the value of linking two data sources to respondent information: interviewer ratings and neighborhood information (measured via census tracts). The utility of an integrative approach is illustrated with data from the Health and Retirement Study. The results reveal modest gains by using a contextualized approach but also demonstrate that neglecting contextual factors may lead to misdirected substantive conclusions, especially for older racial and ethnic minorities. To enhance the ecological validity of survey data, investigators should select theoretically-meaningful contextual data for specific research questions and consider cross-level interactions.     

ELECTROPHYSIOLOGICAL CORRELATES OF STIMULUS EQUIVALENCE PROCESSES

Research reported here concerns neural processes relating to stimulus equivalence class formation. In Experiment 1, two types of word pairs were presented successively to normally capable adults. In one type, the words had related usage in English (e.g., uncle, aunt). In the other, the two words were not typically related in their usage (e.g., wrist, corn). For pairs of both types, event‐related cortical potentials were recorded during and immediately after the presentation of the second word. The obtained waveforms differentiated these two types of pairs. For the unrelated pairs, the waveforms were significantly more negative about 400 ms after the second word was presented, thus replicating the “N400” phenomenon of the cognitive neuroscience literature. In addition, there was a strong positive‐tending wave form difference post‐stimulus presentation (peaked at about 500 ms) that also differentiated the unrelated from related stimulus pairs. In Experiment 2, the procedures were extended to study arbitrary stimulus—stimulus relations established via matching‐to‐sample training. Participants were experimentally näive adults. Sample stimuli (Set A) were trigrams, and comparison stimuli (Sets B, C, D, E, and F) were nonrepresentative forms. Behavioral tests evaluated potentially emergent equivalence relations (i.e., BD, DF, CE, etc.). All participants exhibited classes consistent with the arbitrary matching training. They were also exposed also to an event‐related potential procedure like that used in Experiment 1. Some received the ERP procedure before equivalence tests and some after. Only those participants who received ERP procedures after equivalence tests exhibited robust N400 differentiation initially. The positivity observed in Experiment 1 was absent for all participants. These results support speculations that equivalence tests may provide contextual support for the formation of equivalence classes including those that emerge gradually during testing.     

Mapping the Decision to Quit: A Refinement and Test of the Unfolding Model of Voluntary Turnover

We report a test of an influential theory of employee turnover: the unfolding model ( Lee & Mitchell, 1994 ; Lee, Mitchell, Holtom, McDaniel, & Hill, 1999 ). We describe and critique this classificatory model, and propose both theory‐based and empirical refinements. The two extant tests of the current version of the model have both been with accountants in the United States, so the generalisability of the model is as yet unproven. We present results of an attempt to classify 352 nurse leavers from the United Kingdom's National Health Service using the unfolding model. In contrast to the findings of Lee et al. (1999 ), the model failed to classify a substantial number of nurse leavers, and specific hypotheses derived from the model received only partial support. Classification failures were investigated using both quantitative and qualitative data. Leavers were more likely to be classified if they had no dependants and described their quit as avoidable. Although the unfolding model incorporates more kinds of turnover than traditional turnover models, such systematic classification failure casts doubt on claims that it offers a comprehensive account of turnover. We explain failures with reference to: (i) shortcomings in a key measure; (ii) the characteristics of the occupational group studied; and (iii) the extremely tight labor market for this group of leavers. Nous testons la théorie influente concernant le turnover des salariés: the unfolding model ( Lee & Mitchell, 1994 ; Lee, Mitchell, Holtom, McDaniel & Hill, 1999 ). Après avoir décrit et critiqué ce modèle de classification, nous proposons des améliorations tant au niveau théorique qu’empirique. La version actuelle du modèle a été testée à deux reprises auprès de comptables des Etats‐Unis, aussi ce modèle n’a pas pu être généralisé. Nous présentons les résultats obtenus en utilisant le “unfolding model” auprès de 352 infirmières du service de santé national du Royaume‐Uni qui sont sur le départ. Contrairement aux résultats obtenus par Lee et al. (1999 ), le modèle n’a pas permis de classer un nombre substantiel d’infirmières sur le départ et certaines hypothèses découlant de ce modèle ne reçoivent qu’une validation partielle. Ces échecs de classification ont été analysés tant quantitativement que qualitativement. Il ressort que les sujets étaient plus facilement classés si ils n’avaient aucune personne à charge et si ils décrivaient leur départ comme évitable. Bien que le “unfolding model” incorpore plus de formes de turnover que les modèles traditionnels, un échec de classification aussi systématique questionne quant à sa revendication à offrir une approche complète du turnover. Nous expliquons ces échecs par: (i) des imperfections dans la mesure principale (ii) les caractéristiques du groupe de salariés étudiés (iii) un marché du travail extrêmement difficile pour ce groupe de personnes sur le départ.     

Psychological Factors Associated with Emotional Responses to Receiving Genetic Risk Information

This study identified levels of distress, and predictors of levels of distress, in women undergoing assessment for genetic risk of breast/ovarian cancer based on their family history. It comprised a cohort study following 154 women who completed questionnaires at entry into a cancer genetic assessment programme and following risk provision. Independent significant associates of anxiety following risk provision were age, neuroticism, feeling hopeless about developing cancer, a perceived lack of control over developing cancer, lack of a social confidant, and a coping response involving acceptance/resignation. Depression was associated with age, neuroticism, feeling hopeless about developing cancer, lack of social confidant, and a coping response involving acceptance/resignation. To avoid high levels of psychological morbidity in future cohorts undergoing cancer genetic risk assessment, information should be given that emphasises that some degree of control over health outcomes through behaviour change or increased surveillance is possible.     

Withdrawal Aversion and the Equivalence Test

If a doctor is trying to decide whether or not to provide a medical treatment, does it matter ethically whether that treatment has already been started? Health professionals sometimes find it harder to stop a treatment (withdraw) than to refrain from starting the treatment (withhold). But does that feeling correspond to an ethical difference? In this article, we defend equivalence—the view that withholding and withdrawal of treatment are ethically equivalent when all other factors are equal. We argue that preference for withholding over withdrawal could represent a form of cognitive bias—withdrawal aversion. Nevertheless, we consider whether there could be circumstances in which there is a moral difference. We identify four examples of conditional nonequivalence. Finally, we reflect on the moral significance of diverging intuitions and the implications for policy. We propose a set of practical strategies for helping to reduce bias in end-of-life decision making, including the equivalence test.     

The Multidimensional Nature of Social Cohesion: Psychological Sense of Community, Attraction, and Neighboring

Items from the Neighborhood Cohesion Instrument were completed by 1,732 individuals from a random sample of households in 20 rural communities across Canada during the summer of 2001. Confirmatory factor analysis of the NCI items based on polychoric correlations and weighted least squares estimation found three underlying latent variables. Although items were related to the three latent variables in a somewhat different manner than they were in Buckner's original study, the same three latent variables were evident, providing convincing evidence that social cohesion has at least three subscales: psychological sense of community, neighboring, and attraction. Correlations between subscales were relatively high (between .67 and .87). Intraclass correlation coefficients for the three scales were .115, .127, and .112. In addition, the community means differed on different subscales in a manner that related to recognized characteristics of the communities. Thus the subscales are appropriate measures for both individuals and communities and can be recommended for further research on social cohesion.