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41.
The study investigated the effectiveness of different camouflage designs using a computational image quality index. Camouflaged human targets were presented on a natural landscape and the targets were designed to be similar to the landscape background with different levels of background similarity as estimated by the image index. The targets were presented in front of the observer (central 0 degrees) or at different angles in the left (-7 degrees, -14 degrees, -21 degrees) or right (+7 degrees, +14 degrees, +21 degrees) visual fields. The observer had to detect the target using peripheral vision if the target appeared in the left and right visual fields. The camouflage effectiveness was assessed by detection hit rates, detection times, and subjective ratings on detection confidence and task difficulty. The study showed that the psychophysical measures correlated well with the image similarity index, suggesting a potentially more efficient camouflage effectiveness assessment tool if the relationship between the psychophysical results and the index can be quantified in the future. 相似文献
42.
Heungsun Hwang Hye Won Suk Jang-Han Lee D. S. Moskowitz Jooseop Lim 《Psychometrika》2012,77(3):524-542
We propose a functional version of extended redundancy analysis that examines directional relationships among several sets of multivariate variables. As in extended redundancy analysis, the proposed method posits that a weighed composite of each set of exogenous variables influences a set of endogenous variables. It further considers endogenous and/or exogenous variables functional, varying over time, space, or other continua. Computationally, the method reduces to minimizing a penalized least-squares criterion through the adoption of a basis function expansion approach to approximating functions. We develop an alternating regularized least-squares algorithm to minimize this criterion. We apply the proposed method to real datasets to illustrate the empirical feasibility of the proposed method. 相似文献
43.
Research has documented that children and adolescents with attention-deficit/hyperactivity disorder (ADHD) are at increased
risk of substance use problems. Few studies, however, have focused on early-onset substance use. This study therefore investigated
how the two symptom dimensions of ADHD (hyperactivity/impulsivity and inattention) are associated with early-onset substance
use, the role of persistent ADHD for the association, and to what extent the association is influenced by genetic and environmental
factors. Twins (1,480 pairs) in the Swedish Twin Study of Child and Adolescent Development were followed from childhood to
adolescence. ADHD symptoms were measured at age 8–9 and age 13–14 via parent-report, whereas substance use was assessed at
age 13–14 via self-report. Results revealed that hyperactive/impulsive symptoms predicted early-onset “sometimes” tobacco
use (adjusted odds ratios, 1.12, for one symptom count), controlling for inattentive symptoms and conduct problem behaviors.
There is no independent effect of inattentive symptoms on early-onset substance use. Children with persistent hyperactivity/impulsivity
(defined as scoring above the 75th percentile at both time points) had a pronounced risk of both early-onset tobacco and alcohol
use (adjusted odds ratios from 1.86 to 3.35, compared to the reference group). The associations between hyperactivity/impulsivity
and early-onset substance use were primarily influenced by genetic factors. Our results indicated that hyperactivity/impulsivity,
but not inattention, is an important early predictor for early-onset substance use, and a shared genetic susceptibility is
suggested to explain this association. 相似文献
44.
Cho YS Bae GY Proctor RW 《Journal of experimental psychology. Human perception and performance》2012,38(3):726-734
The present study tested whether coding of tone pitch relative to a referent contributes to the correspondence effect between the pitch height of an auditory stimulus and the location of a lateralized response. When left-right responses are mapped to high or low pitch tones, performance is better with the high-right/low-left mapping than with the opposite mapping, a phenomenon called the horizontal SMARC effect. However, when pitch height is task irrelevant, the horizontal SMARC effect occurs only for musicians. In Experiment 1, nonmusicians performed a pitch discrimination task, and the SMARC effect was evident regardless of whether a referent tone was presented. However, in Experiment 2, for a timbre-judgment task, nonmusicians showed a SMARC effect only when a referent tone was presented, whereas musicians showed a SMARC effect that did not interact with presence/absence of the referent. Dependence of the SMARC effect for nonmusicians on a reference tone was replicated in Experiment 3, in which judgments of the color of a visual stimulus were made in the presence of a concurrent high- or low-pitched pure tone. These results suggest that referential coding of pitch height is a key determinant for the horizontal SMARC effect when pitch height is irrelevant to the task. 相似文献
45.
There is a relatively consistent negative relationship between adolescent depressive symptoms and educational achievement (e.g., grade point average [GPA]). However, the causal direction for this association is less certain due to the lack of longitudinal data with both indicators measured across at least 2 time periods and due to the lack of application of more sophisticated contemporary statistical techniques. We present multivariate results from a large longitudinal cohort-sequential study of high school students (N = 7,317) with measures of self-reported depressive symptoms and self-reported GPAs across multiple time points (following McArdle, 2009, and McArdle, Johnson, Hishinuma, Miyamoto, & Andrade, 2001) using an ethnically diverse sample from Hawai'i. Contemporary statistical techniques included bivariate dynamic structural equation modeling (DSEM), multigroup ethnic and gender DSEMs, ordinal scale measurement of key outcomes, and imputation for incomplete longitudinal data. The findings suggest that depressive symptoms affect subsequent academic achievement and not the other way around, especially for Native Hawaiians compared with female non-Hawaiians. We further discuss the scientific, applied, and methodological-statistical implications of the results, including the need for further theorizing and research on mediating variables. We also discuss the need for increased prevention, early intervention, screening, identification, and treatment of depressive symptoms and disorders. Finally, we argue for utilization of more contemporary methodological-statistical techniques, especially when violating parametric test assumptions. 相似文献
46.
This study examined relations of achievement goals of writers who are speakers of English as a foreign language (EFL), the frequency of their writing strategy use, and the quality of their writing from a multiple goals perspective. The goal profiles of 57 EFL college students with similar writing proficiency were based on rating items of an unpublished scale; Group 1 had strong mastery and strong performance-approach goals, and two groups included students with only one strong mastery (Group 2) or performance (Group 3) goal. Think-aloud protocols indicated that the participants adopted 21 strategies in an argumentative writing task, classified into five categories. Group 1 was found to use writing strategies of monitoring or evaluating, revising, and compensating significantly more often than the other two groups, and produced better essays. Strong mastery and performance-approach goals might be beneficial for EFL college writers. 相似文献
47.
This paper first discusses the relationship between Kullback–Leibler information (KL) and Fisher information in the context
of multi-dimensional item response theory and is further interpreted for the two-dimensional case, from a geometric perspective.
This explication should allow for a better understanding of the various item selection methods in multi-dimensional adaptive
tests (MAT) which are based on these two information measures. The KL information index (KI) method is then discussed and
two theorems are derived to quantify the relationship between KI and item parameters. Due to the fact that most of the existing
item selection algorithms for MAT bear severe computational complexity, which substantially lowers the applicability of MAT,
two versions of simplified KL index (SKI), built from the analytical results, are proposed to mimic the behavior of KI, while
reducing the overall computational intensity. 相似文献
48.
Hasok Chang 《Erkenntnis》2011,75(3):413-429
Why do some epistemic objects persist despite undergoing serious changes, while others go extinct in similar situations? Scientists
have often been careless in deciding which epistemic objects to retain and which ones to eliminate; historians and philosophers
of science have been on the whole much too unreflective in accepting the scientists’ decisions in this regard. Through a re-examination
of the history of oxygen and phlogiston, I will illustrate the benefits to be gained from challenging and disturbing the commonly
accepted continuities and discontinuities in the lives of epistemic objects. I will also outline two key consequences of such
re-thinking. First, a fresh view on the (dis)continuities in key epistemic objects is apt to lead to informative revisions
in recognized periods and trends in the history of science. Second, recognizing sources of continuity leads to a sympathetic
view on extinct objects, which in turn problematizes the common monistic tendency in science and philosophy; this epistemological
reorientation allows room for more pluralism in scientific practice itself. 相似文献
49.
Leanne Chang 《Asian Journal of Social Psychology》2014,17(3):196-205
Guided by the theory of motivated information management, this study investigated the extent to which Singaporean college students' sexual health information‐seeking behaviour could be accounted for by their anxiety of uncertainty discrepancy, their perceived outcomes of information seeking and their perceived confidence in seeking and coping with sexual health information acquired from their best friends. Taking into account that issue relevance may play a role in individuals' health decision‐making, this study also examined the effect of perceived vulnerability on respondents' sexual health information‐seeking behaviour. An online survey was conducted with 202 undergraduate students at a university in Singapore. Respondents were asked to report the frequency with which they sought four types of sexual health information from their best friends: unwanted pregnancy, abortion, HIV/AIDS and other sexually transmitted infections. Survey data showed that respondents' uncertainty discrepancy was positively associated with their anxiety. Anxiety had negative effects on efficacy and outcome expectancy. Outcome expectancy was positively associated with efficacy. Both efficacy and perceived vulnerability accounted for a significant amount of variance in respondents' sexual health information‐seeking behaviour. Findings from this study contribute to a better understanding of young adults' sexual health information behaviour in a Singapore context. 相似文献
50.
Kim Mihye Jasper Andrea D. Lee Jeongmin Won Hyungjoong 《Applied research in quality of life》2022,17(2):469-487
Applied Research in Quality of Life - Empirical studies on work-life balance (WLB) among employees without disabilities are abundant; in contrast, insufficient research exists on WLB and quality of... 相似文献