The Effects of Prior Experience on Estimating the Duration of Simple Tasks.

Previous research provides conflicting evidence regarding the effects of prior experience on estimates of task duration. Research supporting the planning fallacy suggests that people tend to ignore information about their previous task performance, whereas other work indicates that time estimates are influenced by the duration of a just-completed similar task. The present research examined whether information about previous tasks was linked to temporal misestimation on subsequent tasks. Experiment 1 revealed that the accuracy of completion time predictions on an anagram task was influenced by the degree of misestimation in the perceived duration of the preceding task. In Experiment 2, prospective estimates were found to exceed actual time, whereas the direction in which predictions were misestimated (under or overestimation) differed according to the duration of the just-completed task. These findings suggest that taskrelated information is not only used when predicting task duration but also affects temporal misestimation. This research is discussed in the context of bias in predictions of task duration and the allocation of attentional resources in dual task situations in the prospective time estimation paradigm

The triple task technique for studying writing processes : on which task is attention focused ?

The triple task technique measures the time and cognitive effort devoted to specific writing processes by combining directed retrospection with secondary task reaction time (RT). Writing a text is the primary task and rapidly detecting auditory probes to index cognitive effort is the secondary task. The third task is retrospecting and categorizing the contents of working memory at the time of each probe. The present paper reviews studies on the reactivity and validity of the technique. Further, one recent criticism of the method's validity is tested here: namely, that the primary task for the experimenter is not the primary task for the writer, thus distorting the time and effort measurements. We found that time and effort allocated to planning, translating, executing, evaluating, and revising was the same when the writer was encouraged by instructions to focus either on the speed of responding or the accuracy of retrospection instead of the text itself. Because writing requires sustained thought and attention to produce a cumulative product, it is apparently difficult to make text production anything but the primary task. The triple task technique offers a useful alternative to pause analysis and verbal protocols for investigating the functional features of writing

Effect of time span and task load on pilot mental workload

Two sets of experiments were run to examine how the mental workload of a pilot might be measured. The effects of continuous manual control activity versus discrete assigned mental tasks (including the length of time between receiving an assignment and executing it) were examined. The first experiment evaluated the strengths and weaknesses of measuring mental workload with an objective perforamance (altitude deviations) and five subjective ratings (activity level, complexity, difficulty, stress, and workload). The second set of experiments built upon the first set by increasing workload intensities and adding another performance measure: airspeed deviation. The results are discussed for both low and high experience pilots

Effect of time span and task load on pilot mental workload

Two sets of simulations designed to examine how a pilot's mental workload is affected by continuous manual-control activity versus discrete mental tasks that included the length of time between receiving an assignment and executing it are described. The first experiment evaluated two types of measures: objective performance indicators and subjective ratings. Subjective ratings for the two missions were different, but the objective performance measures were similar. In the second experiments, workload levels were increased and a second performance measure was taken. Mental workload had no influence on either performance-based workload measure. Subjective ratings discriminated among the scenarios and correlated with performance measures for high-workload flights. The number of mental tasks performed did not influence error rates, although high manual workloads did increase errors

Determiners of accuracy when making an expected duration estimation: The role of ‘past’ event/task saliency

One of the important ‘skills’ which is associated with effective time management is the ability to accurately estimate the probable duration of a to-be-scheduled event or task. The present study explored the effect that presenting a highly salient, similar to-be-estimated task had on a subsequent task estimate. Participants in this experiment tended to allocate significantly less time to the completion of a task if they had previously estimated the expected duration of a similar, shorter task. Conversely, they tended to allocate significantly more time to the completion of a task if they had previously estimated the expected duration of a similar but longer task. The results are discussed in relation to future developments in scheduling/time management software