无边界职业生涯时代的就业能力:一种新的心理契约

在无边界职业生涯时代,以雇员忠诚换取就业保障为特征的心理契约,正逐步被以绩效换取就业能力为特征的新的心理契约所取代。基于就业能力的心理契约管理要求组织通过沟通了解员工的期望和态度,给员工以更多的知识积累和学习机会,实施合理的组织策略,提升员工的就业能力。     

Postcategorical filtering in a bar-probe task

Memory &; Cognition - To investigate the causes of errors in partial-report bar-probe tasks, a set of (color) stimuli that allowed the use of a new method of analysis was devised. With these...     

The array size function in simple visual search tasks: A comparison between “go-no go” and “yes-no” tasks under conditions of high and low target-noise similarity

Summary In research on visual search within a single eye-fixation a number of different tasks are used and referred to interchangeably. Research with other types of tasks suggests that there are possibly important differences between these tasks. In the present study, two types of search tasks were compared under conditions as equal as possible: the go-no go task and the yes-no task. Conditions of low and high target-noise similarity were used. The results obtained showed: a) a steeper slope of the array size function in yes-no tasks than in go-no go tasks on the first day of practice but not on the second: b) a higher intercept value of the same function for yes-no tasks than for go-no go tasks; and c) a greater proportion of errors with yes-no tasks than with comparable go-no go tasks. A tentative model, describing the main features of the results obtained, is briefly sketched.     

Sources of position-perception error for small isolated targets

It has often been reported that, in the presence of static reference stimuli, briefly presented visual targets are perceived as being closer to the fixation point than they actually are. The first purpose of the present study was to investigate whether the same phenomenon can be demonstrated in a situation without static reference stimuli. Experiment 1, with position naming as the task, showed that such a central shift is also observed under these conditions. This finding is of importance because it completes an explanation for central near-location errors in the partial-report bar-probe task. The second purpose of the present study was to provide an explanation for these central shifts. For this explanation information about the exact size of the central shift is required. In Exps. 2, 3, and 4, with cursor setting as the task, it was attempted to assess more precisely the size of the central shifts. These experiments revealed that two different factors determine the results in cursor setting tasks; a factor “target position” and a factor “cursor position.” Experiment 5 showed that it is the point of fixation, not the fixation point, that serves, at least in part, as the reference point in this type of task. All the findings together allow us to conclude that the target positions are underestimated by about 10%. From vision research it is known that saccadic eye movements, performed for bringing a target in the fovea, also show an undershoot of about 10%. It is therefore concluded that the system in charge of saccadic eye movements also provides the metric in visual space within a single eye fixation. Received: 11 February 1998 / Accepted: 25 June 1998     

Some evidence for a selfterminating process in simple visual search tasks

Two experiments were conducted to investigate the unsettled question of whether the visual search process is selfterminating or exhaustive. In the experiments three letters were placed on an imaginary circle round the fixation point. Two different letters were used, one of which was defined as the ‘signal’. Ss had to respond ‘yes’ when one or more signals were in the display, ‘no’ otherwise. In both experiments the number of signals in the display was varied from 0 to 3.Decreasing latencies with increasing number of signals were observed in both experiments, indicating a selfterminating visual search. In experiment 1 a significant increase in latencies with increasing visual angle was found, in experiment 2 an increase in latency resulting from neighbouring contours. Both factors probably contribute to the slope of the function relating positive responses to display size and to the slope of the function relating negative responses to display size when stimuli are presented in linear arrays as in the experiment by Atkinson et al. (1969). As a result the slopes become more equal, falsely suggesting an exhaustive visual search process.     

On selection in vision

Summary The discrepancy between the capabilities of perceptual systems and effector systems makes mechanisms necessary that can selectively designate a subset of the perceptual information available to control an action. In vision, since foveation is neither sufficient nor necessary for this selection, central selection mechanisms have to be postulated. This study is concerned with the question of at what level this central selection takes place in one type of task, the partial-report bar-probe task. Two theories are relevant: early selection theories, asserting that central selection operates in a stage containing rapidly decaying precategorical visual information, and late selection theories, arguing that central selection operates in a stage containing abstract categorical information. A prediction following from the assumptions of early selection theories, but not of late selection theories, is that in bar-probe tasks the function relating the number of visual confusions to probe delays has to exhibit an inverted-U shape. This prediction was tested in five experiments, two with colors as items and three with letters. In all experiments, the proportion of visual confusions first increased with increasing probe delays and then decreased with still larger probe delays. The results support the early selection theories for small probe delays. For larger probe delays, late selection has to be postulated.     

Attending to color with proper fixation

In contemporary theorizing, there is a controversy about the role of spatial location in the selection of visual information; some theories postulate that position plays a unique role, whereas other theories hold that position is just one selection dimension that is not different from other dimensions, such as color and shape. In this context, a paradigm introduced by Tsal and Lavie (1988) promised to be of fundamental importance. With that paradigm, Tsal and Lavie found that, after reporting a first letter of a prespecified color, subjects preferred to switch their reporting to letters from array positions adjacent to that letter over continuing to report letters of the same color as that of the first letter. This switch from color to position provided firm evidence in favor of the “position-special” views as opposed to the “all-attributes-are-equal” views. In the present study, six experiments, employing Tsal and Lavie’s paradigm and variations of that paradigm, are reported. Experiments 1, 2, 4, and 5 show that evidence for a switch from selection on the basis of color to selection on the basis of position is not obtained when subjects are forced to fixate the fixation point and possibly also not under normal contrast conditions without fixation controls. Experiment 3 shows that switching from color to position is difficult. Experiments 2, 5, and 6 show that evidence for a switch is obtained only under low-contrast conditions when subjects are not forced to fixate the fixation point. It is concluded that the Tsal and Lavie paradigm is an asymmetric paradigm. The results reported by Tsal and Lavie constituted a major threat for the “all-attributes-are-equal” theories and provided firm support for the “position-special” theories. The results reported in the present study are compatible with the all-attributes-are-equal theories, but, at the same time, do not constitute a major threat for the contemporary position-special theories.