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901.
In this paper, we describe software that turns a Macintosh computer into an off-the-shelf tool for experiments on visual search. Our design goals included portability (between members of the Macintosh computer family and between various research settings), user-friendliness (equivalent to Macintosh programming standards), flexibility (to allow replication and extension of important experiments on visual search), and adaptability (very short design-to-data and data-to-analysis turnaround times). We describe how the software meets these goals in three major phases of an experiment: stimulus construction, experimental control, and statistical analysis. We then list several landmark studies of visual search that can be easily designed and extended with the software. Finally, we outline plans for expanding the experimental variations that will be supported in future versions of the software.  相似文献   
902.
903.
Phonetic segments are coarticulated in speech. Accordingly, the articulatory and acoustic properties of the speech signal during the time frame traditionally identified with a given phoneme are highly context-sensitive. For example, due to carryover coarticulation, the front tongue-tip position for HI results in more fronted tongue-body contact for a /g/ preceded by /l/ than for a /g/ preceded by /r/. Perception by mature listeners shows a complementary sensitivity—when a synthetic /da/-/ga/ continuum is preceded by either /al/ or /ar/, adults hear more /g/s following HI rather than Irl. That is, some of the fronting information in the temporal domain of the stop is perceptually attributed to /l/ (Mann, 1980). We replicated this finding and extended it to a signaldetection test of discrimination with adults, using triads of disyllables. Three equidistant items from a /da/-/ga/ continuum were used preceded by /al/ and /ar/. In the identification test, adults had identified item ga5 as “ga”, and dal as “da”, following both /al/ and /ar/, whereas they identified the crucial item d/ga3 predominantly as “ga” after /al/ but as “da” after /ar/. In the discrimination test, they discriminated d/ga3 from dal preceded by /al/ but not /ar/; compatibly, they discriminated d/ga3 readily from ga5 preceded by /ar/ but poorly preceded by /al/. We obtained similar results with 4-month-old infants. Following habituation to either ald/ga3 or ard/ga3, infants heard either the corresponding ga5 or dal disyllable. As predicted, the infants discrimi-nated d/ga3 from dal following /al/ but not /ar/; conversely, they discriminated d/ga3 from ga5 following /ar/ but not /al/. The results suggest that prelinguistic infants disentangle consonant-consonant coarticulatory influences in speech in an adult-like fashion.  相似文献   
904.
Growth systematically changes the body proportions of both humans and animals so that the ratio of head height to body height decreases with age. Prior studies have demonstrated that body proportions provide effective information for age perception. To test the proposal that illustrators incorporate this information into their drawings, measurements were made of the head and body heights of 100 pairs of animals appearing in children’s picture books. In 93 pairs, the animal intended to be perceived as older had a smaller head-to-body ratio than did the younger animal. Ratings collected for 25 of these pairs showed that both perceived age and cuteness are significantly correlated with body proportions. The magnitudes of the correlations were only modest, suggesting that other aspects of the drawings influenced perceived age and cuteness. In addition, observers reported that body proportions are only one of a variety of factors influencing age and cuteness perception. As has been found in other studies, perceived age and cuteness were negatively correlated.  相似文献   
905.
State lawmakers in Virginia recently approved a measure to limit to one the number of handguns a person can purchase within a thirty day period. In the months preceding the law's approval, a survey was conducted to measure the level of public support for the proposed initiative. The results of the survey were provided to lawmakers and other high level government officials in an effort to provide policymakers with objective data for gauging support (or non-support) for the proposal. Past public opinion polls which have measured attitudes concerning gun control reveal differences in the levels of support with regard to such factors as individual gun ownership and region of residence. The following research reveals the sentiment of one State's citizenry toward a specific handgun control measure by focusing on how responses varied across selected sub-groups within the sample.  相似文献   
906.
Briefly stated my point is that the well-being of each person in a community conceived abstractly may be all too easily sacrificed for the sake of the abstraction. Physicians may offer critically ill patients places in programs of experimental treatment, but there is commonly a catch to the offer. To take part in a program of clinical experiment a patient must not only risk a possible failure of a fresh drug and the chance of destructive side effects from the drug, but the patients must risk only getting the traditional treatment along with a placebo rather than the experimental drug. Placebo control, double blind critical protocols for testing effects of fresh drugs on critically ill patients are a commonplace. I question the scientific objectivity of the protocols and the underlying ethic, and suggest use of alternate protocols. Experimental tests in the treatment gram-negative bacteria blood infections, muscular dystrophy, and AIDS and AIDS-related diseases are examples.  相似文献   
907.
This article reviews the results of survey methodological research that illustrate phenomena of potential interest to investigators of memory, and also reviews psychological research designed to explore some of these phenomena under controlled laboratory conditions. We classify the phenomena reviewed into broad categories of remembering what events occurred, remembering when events occurred, and estimation and reconstruction processes used in reporting recurring events. We delineate the contributions of this research for our understanding of memory phenomena and show where this research has revealed gaps in our existing theories and knowledge. These findings present challenges for future collaboration between cognitive psychologists and survey methodologists.  相似文献   
908.
909.
This study explores Black teachers' preferences for and ratings of consultant effectiveness as a function of consultant race, consultant style, and teacher stage of racial identity development. No significant differences were noted in preferences for either a same- or opposite-race consultant. Participants preferred and rated as more effective an instrumentally oriented consultant.  相似文献   
910.
This study examined the effects of neurolinguistic mirroring versus nonmirroring of selected nonverbal behaviors on empathy, trustworthiness, and positive interaction in a cross-cultural setting among 60 Choctaw adolecents and Caucasian female counselors. Results indicated significant mirroring effects on the empathy scale of the Barrett-Lennard Relationship Inventory.  相似文献   
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