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41.
Leventhal Adam M.; Waters Andrew J.; Boyd Susan; Moolchan Eric T.; Lerman Caryn; Pickworth Wallace B. 《Canadian Metallurgical Quarterly》2007,15(1):21
Gender differences in tobacco withdrawal are of considerable clinical importance, but research findings on this topic have been mixed. Methodological variation in samples sizes, experimental design, and measures across studies may explain the inconsistent results. The current study examined whether male (n = 101) and female (n = 102) smokers (≥15 cigarettes/day) differed in abstinence-induced changes on a battery of self-report measures (withdrawal, affect, craving), cognitive performance tasks (attention, psychomotor performance), and physiological responses (heart rate, blood pressure, brain electroencephalogram). Participants attended 2 counterbalanced laboratory sessions, 1 following 12 hr of abstinence and the other following ad libitum smoking. Results showed that women reported greater abstinence-induced increases in negative affect, withdrawal-related distress, and urge to smoke to relieve withdrawal distress. In contrast, both genders reported similar abstinence-induced changes in positive affect and urge to smoke for pleasure. Men and women exhibited generally similar abstinence-induced changes in physiological and cognitive performance measures. In addition, gender did not moderate the association between withdrawal symptoms and baseline measures of smoking behavior and dependence. Abstinence-induced changes in withdrawal distress mediated the effect of gender on latency until the 1st cigarette of the day at trend levels ( p 相似文献
42.
Gender recognition has been playing a very important role in various applications such as human–computer interaction, surveillance, and security. Nonlinear support vector machines (SVMs) were investigated for the identification of gender using the Face Recognition Technology (FERET) image face database. It was shown that SVM classifiers outperform the traditional pattern classifiers (linear, quadratic, Fisher linear discriminant, and nearest neighbour). In this context, this paper aims to improve the SVM classification accuracy in the gender classification system and propose new models for a better performance. We have evaluated different SVM learning algorithms; the SVM‐radial basis function with a 5% outlier fraction outperformed other SVM classifiers. We have examined the effectiveness of different feature selection methods. AdaBoost performs better than the other feature selection methods in selecting the most discriminating features. We have proposed two classification methods that focus on training subsets of images among the training images. Method 1 combines the outcome of different classifiers based on different image subsets, whereas method 2 is based on clustering the training data and building a classifier for each cluster. Experimental results showed that both methods have increased the classification accuracy. 相似文献
43.
互联网技术不断发展,新浪微博作为公开的网络社交平台拥有庞大的活跃用户. 然而由于用户数量庞大,且个人信息并不一定真实,造成训练样本打标困难. 本文采用了一种多视图tri-training的方法,构建三个不同的视图,利用这些视图中少量已打标样本和未打标样本不断重复互相训练三个不同的分类器,最后集成这三个分类器实现用户性别判断. 本文用真实用户数据进行实验,发现和单一视图分类器相比,使用多视图tri-training学习训练后的分类器准确性更好,且需要打标的样本更少. 相似文献
44.
针对以往仅用人脸特征或头发特征来进行性别分类的片面性,提出了将两类特征相融合的性别分类方法.用对光照、尺度变化具有很强鲁棒性的Gabor小波变换提取人脸内部特征并用PCA方法降维.利用最小代价原理,将动态搜索技术用于图像空间取得头发区域,定义了头发长度、头发表面积两种外部特征,并提出了相应的特征提取方法.采用模糊神经网络对三种特征进行非线性融合.在 Essex 人脸库中进行了性别分类实验,取得了97.1%的准确率. 相似文献
45.
Over the past decade, the call to foster computational thinking (CT) in every child has received considerable attention. However, there is little understanding of whether children are developmentally ready to think computationally and what specific CT concepts and skills can be developed at various ages. This study explored the developmental and gender differences in CT skills of 197 Grade 4–6 students (aged 9–13) before being exposed to instruction and investigated the age–gender interaction effects on their CT acquisition in an intervention combining both programming and non-programming (unplugged) activities. Results show that students' CT skills followed a developmental progression before instruction. Gender difference across ages was insignificant in conditionals, logical operators, pattern recognition and generalization skills. Additionally, students of different ages developed CT differently during the intervention, and their CT acquisition was unaffected by gender. Implications for practice and research in CT education were discussed. 相似文献
46.
LUO Wen-bin 《数字社区&智能家居》2008,(27)
随着电脑的普及和因特网(Internet)的快速发展和运用,在我们的生活中,产生了一种新的重要的交流手段——网上在线聊天。现实中流传着"网络无性别"的观点。该文针对这一观点,对网上在线聊天语言进行了初步的分析,从而发现在网上依然存在性别话语差异。男女性不同的在线会话风格,是他们面对面交际会话性别差异的延伸。 相似文献
47.
Charyton Christine; Jagacinski Richard J.; Merrill John A. 《Canadian Metallurgical Quarterly》2008,2(3):147
Psychology and engineering faculty developed a new assessment tool to measure creativity in engineering design (Creative Engineering Design Assessment or CEDA). Fifty-eight engineering students (52 men and 6 women) and 59 psychology students (27 men and 32 women) completed the CEDA as well as other general creativity measures (creative personality, creativity temperament, and cognitive risk tolerance). Interrater reliability for the overall CEDA was high (r = .98). On average, men and women displayed similar levels of creative personality, cognitive risk tolerance, and engineering creativity (CEDA scores). However, the CEDA scores exhibited a cross-over interaction between academic class (engineering and psychology) and gender. Women displayed more creativity temperament. Intertest correlations indicate that the CEDA is different from the other general creativity measures. These results suggest that engineering design creativity may be a specialized skill that needs to be honed in engineering students. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Data in this study supported a model of internalization that included both transmission and transactional variables. Two sets of hierarchical linear regression models were conducted on data collected from the fathers, mothers, and adolescents (10–12 yrs old) in 171 intact Caucasian families. One set predicted adolescent religious behavior; the other predicted the importance of religion to child. Transmission variables (parental religious behavior and parental desire for child to be religious) predicted the most variance in all models. Dyadic discussions of faith (transactional) predicted significant variance in all models. Child gender had a direct effect only on adolescent religious behavior. A significant 3-way interaction occurred between child gender, parental desire for child to be religious, and dyadic discussions when predicting importance of religion to child, with child and parent gender dyads interacting in a complex manner. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Atkins David C.; Baucom Donald H.; Jacobson Neil S. 《Canadian Metallurgical Quarterly》2001,15(4):735
Infidelity is a common phenomenon in marriages but is poorly understood. The current study examined variables related to extramarital sex using data from the 1991-1996 General Social Surveys. Predictor variables were entered into a logistic regression with presence of extramarital sex as the dependent variable. Results demonstrated that divorce, education, age when first married, and 2 "opportunity" variables--respondent's income and work status--significantly affected the likelihood of having engaged in infidelity. Also, there were 3 significant interactions related to infidelity: (a) between age and gender, (b) between marital satisfaction and religious behavior, and (c) between past divorce and educational level. Implications of these findings and directions for future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Feldstein Ewing Sarah W.; Hendrickson Stacey M. L.; Payne Nanetta S. 《Canadian Metallurgical Quarterly》2008,22(4):587
This study evaluated the validity of the Desired Effects of Drinking Scale (DEoDS) with a late adolescent sample. This brief measure (37 items) was designed to assess reasons for drinking across 9 domains. Across a culturally diverse sample of late adolescents (ages 18-20 years), this measure evidenced high internal consistency, particularly when all items were summed in 1 full-scale score. Contrary to the factors found with adults, 8 factors emerged with this sample. No differences were found by culture, providing initial evidence for the cross-cultural validity of this measure. In addition, gender differences emerged for only 1 factor. Overall, the results provide empirical support for the use of this measure to assess late adolescents' and emerging adults' reasons for drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献