The effects of maternal employment and non-maternal infant care on development at two and four years

Differences in maternal employment during children's first year of life and children's entry into non-maternal care before the age of 1 year failed to predict differences in cognitive and socioemotional development at 2 and 4 years of age, after family background variables were controlled. Two samples were studied: a population sample of 1100 Bermudian children and a smaller subsample of children most of whom were determined to be at risk for developmental problems. To assess the effects of maternal employment, we compared infants with mothers who worked 20 or more hours a week to infants with mothers who worked less than 20 hours a week. To assess the effects of entry into non-maternal care before the age of one, we compared infants who were placed in regular non-maternal care before the age of one versus infants who did not experience regular non-maternal care before the age of one. The results revealed that family background variables frequently predicted many child outcome measures in both the total sample and the smaller research sample. After controlling for family characteristics, no differences were found between children whose mothers worked 20 or more hours a week when they were infants and children with mothers who worked less than 20 hours a week in either sample. In addition, age of entry into non. maternal care before the age of one did not significantly predict any child outcome measures.     

Driving assessment with computer-video scenarios: More is sometimes better

Several factors are critical in designing effective simulator systems for driving research and driver assessment. First, there is cost, in terms of which, less is better. Costly systems are sometimes fine for specific research purposes, but they are impractical for most other purposes. Second, there is realism; in this case, more may be better, but we don’t know how much realism is really necessary for good prediction of actual driving behaviors. Recent evidence suggests that real-world clutter may enhance prediction, but it also makes interpreting research more difficult. More realism may increase cost, but this is not necessarily the case. Third, there is user-friendliness, in terms of which, again, more is better. Systems that are easier to operate require less-highly trained personnel; hence, increasing user-friendliness also decreases cost, especially for assessment. We demonstrated a highly user-friendly, low-cost, moderately realistic, and partly interactive computer-video driving research and assessment system. In recent research, we obtained multipleR values ofA7 for older drivers with only three to four scenarios predicting a real-world crash index.     

Sensitivity to combinations of musical parameters: Pitch with duration,and pitch pattern with durational pattern

In four experiments, listeners’ sensitivity to combinations of pitch and duration was investigated. Experiments 1–3 involved “textures” of notes, which were created by repeatedly sounding one of two notes (e.g., C₄ quarter note; D₄ eighth note), so that each note had an equal chance of occurring at any point within a texture. Experiment 1 showed that if a texture change was effected by introducing a pitch or duration that was not in the initial texture, the change was perceived by both attentive and distracted listeners. If a texture change was effected by combining the pitch of one note with the duration of the other note in the initial texture, and vice versa, it was perceived only if the listeners were attentive. Sensitivity to pitch/duration combinations was poorer when the pitch difference between component notes of textures was increased (Experiment 2), but it was better when the difference in duration between component notes was increased (Experiment 3). In Experiment 4, listeners’ sensitivity to combinations of pitch pattern and durational pattern in brief sequences was examined. Listeners were sensitive to the manner in which parameter patterns were combined when they were attentive, but not when they were distracted. The results are discussed in view of featureintegration theory and its application to music cognition.     

The calibration and resolution of confidence in perceptual judgments

Carleton University, Ottawa, Ontariot Canada Confidence rating based calibration and resolution indices were obtained in two experiments requiring perceptual comparisons and in a third with visual gap detection. Four important results were obtained. First, as in the general knowledge domain, subjects were underconfident when judgments were easy and overconfident when they were difficult. Second, paralleling the clear dependence of calibration on decisional difficulty, resolution decreased with increases in decision difficulty arising either from decreases in discriminability or from increasing demands for speed at the expense of accuracy. Third, providing trial-by-trial response feedback on difficult tasks improved resolution but had no effect on calibration. Fourth, subjects can accurately reportsubjective errors (i.e., trials in which they have indicated that they made an error) with their confidence ratings. It is also shown that the properties of decision time, conditionalized on confidence category, impose a rigorous set of constraints on theories of confidence calibration.     

Novel popout with nonsense strings: Effects of predictability of string length and spatial location

Recent studies have shown that when one of four expected words is replaced by a single unexpected word, the unexpected word may capture attention. In three experiments, we explored the generality of this effect. In each experiment, observers viewed arrays composed of four computergenerated “nonsense” strings. Accuracy of string localization was assessed after each array. Some strings, calledfamiliar, appeared in many arrays, whereas others, callednovel, appeared in only one. In each experiment, novel strings in arrays composed of one novel and three familiar strings were localized more accurately than were novel strings in arrays composed entirely of novel strings, and familiar strings in these arrays were localized less accurately than were familiar strings in arrays composed entirely of familiar strings. These two effects, termednovel popout andfamiliar sink-in, respectively, were observed even when novel and familiar strings were rendered less discriminable by holding their lengths constant (Experiment 2) and when familiar strings always appeared in the same spatial locations (Experiment 3). The data suggest that novel objects can capture attention even when the objects lack any clear linguistic referent, when they are superficially similar to the familiar objects that surround them, and when the spatial locations of familiar objects are completely predictable.     

USING REINFORCEMENT-BASED METHODS TO ENHANCE MEMBERSHIP RECRUITMENT IN A VOLUNTEER ORGANIZATION

The present study employed reinforcement-based methods to induce existing members to recruit new members to join a chamber of commerce. Three interventions took place during June and July of 3 successive years. The investigators trained chamber leaders to use reinforcement methods (e.g., contingent tokens) to reinforce recruitment and dues collections. All three interventions produced substantial increases in their targets.