“Tell me more about this…”: An examination of the efficacy of follow-up open questions following an initial account

In information gathering interviews, follow-up questions are asked to clarify and extend initial witness accounts. Across two experiments, we examined the efficacy of open-ended questions following an account about a multi-perpetrator event. In Experiment 1, 50 mock-witnesses used the timeline technique or a free recall format to provide an initial account. Although follow-up questions elicited new information (18–22% of the total output) across conditions, the response accuracy (60%) was significantly lower than that of the initial account (83%). In Experiment 2 (N = 60), half of the participants received pre-questioning instructions to monitor accuracy when responding to follow-up questions. New information was reported (21–22% of the total output) across conditions, but despite using pre-questioning instructions, response accuracy (75%) was again lower than the spontaneously reported information (87.5%). Follow-up open-ended questions prompt additional reporting; however, practitioners should be cautious to corroborate the accuracy of new reported details.     

Rejoinder: Remaining Challenges in Investigating Grade-Retention Effectiveness

This rejoinder, in response to the commentaries of Steiner, Park, and Kim (this issue) and Reshetnyak, Cham, and Hughes (this issue), discusses remaining challenges in grade retention research. First, a same-age comparison assumes that the instruments used in different grades measure ability equally well. We discuss the importance of evaluating the properties of the scaling process to address whether this assumption has been met. Second, we discuss issues in the selection of covariates to be included in the weights. Third, we discuss the unconfoundedness assumption and the problem of remaining imbalance. Finally, we provide an empirical illustration showing that studying grade-retention effectiveness comes with multiple methodological decisions that are rooted in a bias–variance trade-off.     

Culture impacts the magnitude of the emotion-induced memory trade-off effect

The present study assessed the extent to which culture impacts the emotion-induced memory trade-off effect. This trade-off effect occurs because emotional items are better remembered than neutral ones, but this advantage comes at the expense of memory for backgrounds such that neutral backgrounds are remembered worse when they occurred with an emotional item than with a neutral one. Cultures differ in their prioritisation of focal object versus contextual background information, with Westerners focusing more on objects and Easterners focusing more on backgrounds. Americans, a Western culture, and Turks, an Eastern-influenced culture, incidentally encoded positive, negative, and neutral items placed against neutral backgrounds, and then completed a surprise memory test with the items and backgrounds tested separately. Results revealed a reduced trade-off for Turks compared to Americans. Although both groups exhibited an emotional enhancement in item memory, Turks did not show a decrement in memory for backgrounds that had been paired with emotional items. These findings complement prior ones showing reductions in trade-off effects as a result of task instructions. Here, we suggest that a contextual-focus at the level of culture can mitigate trade-off effects in emotional memory.     

Notes and Comments the Role of Action Feedback in the Acquisition of Simple Motor Responses

The use of visual action feedback (AIF) in learning a simple motor response can sometimes be as effective as the more conventional terminal feedback (TIF) but sometimes leads to gross overshooting errors when AIF is removed. Both the amplitude of movement and the gain of the AIF have strong and systematic effects on the error in attempted reproductions. Percent overestimation increases linearly with fog. gain and decreases linearly with log. amplitude. This may be due to an intersensory effect in which visual and kinesthetic feedback sum to form a unitary impression of the movement on which subsequent attempts at reproduction are based.     

The moderating effect of motivation on health-related decision-making

Objective: This study identifies how autonomous and controlled motivation moderates the cognitive process that drives the adoption of personalised nutrition services. The cognitive process comprises perceptions of privacy risk, personalisation benefit, and their determinants.

Design: Depending on their level of autonomous and controlled motivation, participants (N = 3453) were assigned to one of four motivational orientations, which resulted in a 2 (low/high autonomous motivation) × 2 (low/high controlled motivation) quasi-experimental design.

Results: High levels of autonomous motivation strengthened the extent to which: (1) the benefits of engaging with a service determined the outcome of a risk-benefit trade-off; (2) the effectiveness of a service determined benefit perceptions. High levels of controlled motivation influenced the extent to which: (1) the risk of privacy loss determined the outcome of a risk-benefit trade-off; (2) controlling personal information after disclosure and perceiving the disclosed personal information as sensitive determined the risk of potential privacy loss.

Conclusion: To encourage the adoption of personalised dietary recommendations, for individuals with high levels of autonomous motivation emphasis should be on benefits and its determinants. For those with high levels of controlled motivation, it is important to focus on risk-related issues such as information sensitivity.     

Estimating the growth of internal evidence guiding perceptual decisions

Perceptual decision-making is thought to involve a gradual accrual of noisy evidence. Temporal integration of the evidence reduces the relative contribution of dynamic internal noise to the decision variable, thereby boosting its signal-to-noise ratio. We aimed to estimate the internal evidence guiding perceptual decisions over time, using a novel combination of external noise and the response signal methods. Observers performed orientation discrimination of patterns presented in external noise. We varied the contrast of the patterns and the delay at which observers were forced to signal their decision. Each test stimulus (patterns and noise sample) was presented twice. Across two experiments we varied the availability of the visual stimulus for processing. Observer model analyses of discrimination accuracy and response consistency to two passes of the same stimulus, suggested that there was very little growth in the internal evidence. The improvement in accuracy over time characterised by the speed-accuracy trade-off function predominantly reflected a decreasing proportion of non-visual decisions, or pure guesses. There was no advantage to having the visual patterns visible for longer than 80 ms, indicating that only the visual information in a short window after display onset was used to drive the decisions. The remarkable constancy of the internal evidence over time suggests that temporal integration of the sensory information was very limited. Alternatively, more extended integration of the evidence from memory could have taken place, provided that the dominant source of internal noise limiting performance occurs between-trials, which cannot be reduced by prolonged evidence integration.     

Learning to allocate limited time to decisions with different expected outcomes

The goal of this article is to investigate how human participants allocate their limited time to decisions with different properties. We report the results of two behavioral experiments. In each trial of the experiments, the participant must accumulate noisy information to make a decision. The participants received positive and negative rewards for their correct and incorrect decisions, respectively. The stimulus was designed such that decisions based on more accumulated information were more accurate but took longer. Therefore, the total outcome that a participant could achieve during the limited experiments’ time depended on her “decision threshold”, the amount of information she needed to make a decision. In the first experiment, two types of trials were intermixed randomly: hard and easy. Crucially, the hard trials were associated with smaller positive and negative rewards than the easy trials. A cue presented at the beginning of each trial would indicate the type of the upcoming trial. The optimal strategy was to adopt a small decision threshold for hard trials. The results showed that several of the participants did not learn this simple strategy. We then investigated how the participants adjusted their decision threshold based on the feedback they received in each trial. To this end, we developed and compared 10 computational models for adjusting the decision threshold. The models differ in their assumptions on the shape of the decision thresholds and the way the feedback is used to adjust the decision thresholds. The results of Bayesian model comparison showed that a model with time-varying thresholds whose parameters are updated by a reinforcement learning algorithm is the most likely model. In the second experiment, the cues were not presented. We showed that the optimal strategy is to use a single time-decreasing decision threshold for all trials. The results of the computational modeling showed that the participants did not use this optimal strategy. Instead, they attempted to detect the difficulty of the trial first and then set their decision threshold accordingly.     

Task specificity and the timing of discrete aiming movements

In discrete aiming movements the task criteria of time-minimization to a spatial target (e.g., Fitts, 1954) and time-matching to a spatial-temporal goal (e.g., Schmidt et al., 1979) tend to produce different functions of the speed-accuracy trade-off. Here we examined whether the task-related movement speed-accuracy characteristics were due to differential space-time trade-offs in time-matching, velocity-matching and time-minimizing task goals. Twenty participants performed 100 aiming trials for each of 15 combinations of task-type (3) and space-time condition (5). The prevalence of the primary types of sub-movement (none, pre-peak, post-peak, undershooting and overshooting) was determined from the kinematics of the movement trajectory. There were comparable distributions of trajectory sub-movement profiles and space-time movement outcomes across the three tasks at the short movement duration that became increasingly dissimilar over decreasing movement velocity and increasing movement time conditions. Movement time was the most influential variable in mediating sub-movement characteristics and the spatial/temporal outcome accuracy and variability of discrete aiming tasks – a role that was magnified in the explicit task demands of time-matching. The time-matching and time-minimization task goals in discrete aiming induce qualitatively different control processes that progressively contribute beyond the minimal time conditions to task-specific space-time accuracy and variability characteristics of the respective movement speed-accuracy functions.     

词间空格促进从右向左呈现汉语文本的阅读

摘要：为探讨在无阅读经验时,词切分线索是否促进读者的阅读与词汇识别,本研究操纵了阅读方向、词切分线索与目标词的词频。采用眼动仪记录读者的阅读过程。结果发现：阅读方向与词切分线索的交互作用显著,词切分显著地促进了从右向左呈现文本的阅读,但并不影响阅读从左向右呈现的文本;词切分条件下目标词的注视时间显著地短于无词切分条件。表明词切分线索促进了无阅读经验时的阅读,支持词切分线索的促进与文本不熟悉干扰之间权衡作用的假设。     

Violations of Fitts’ Law in a Ballistic Task

ABSTRACT

The authors explored changes in the postural preparation and movement times during jumps into targets of different sizes placed at different distances from the participant. Both movement and preparation times scaled with movement distance. Neither movement nor preparation time showed an effect of target size, although preparation time showed a tendency to increase for smaller targets. These observations show that the classical Fitts’ law can be violated in tasks that involve a ballistic component. The data corroborate a hypothesis that Fitts’ law originates at the level of movement planning.