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261.
The transition to parenthood is a period of both joy and challenge for most parents. There is a recognized need to support parents during this period, yet existing interventions have shown limited evidence of efficacy. This study takes a consumer‐focused approach to examine the needs and preferences of parents both prenatally (n = 77) and postnatally (n = 123) for parenting support. The study used a cross‐sectional design with a purpose‐built online survey. Parents were recruited via online forums, Facebook and parenting blogs, childcare centers, and playgroups. In general, all parents were satisfied with their current levels of both formal and informal support, and about one fourth of parents had accessed a parenting intervention. Parents expressed a moderate level of interest in additional parenting information, and parents expecting their first baby indicated preferences for information about basic baby care needs whereas postnatally, parents expressed more interest in topics around self‐care and behavior management. The implications for developing interventions and engaging families are discussed.  相似文献   
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B2C电子商务中消费者的风险来源及其影响   总被引:10,自引:0,他引:10  
研究目的是通过考察B2C(Business to Consumer)电子商务中消费者知觉到的风险来源来验证电子商务交易中的虚实界面假设。通过访谈法和问卷法调查了337名被试,探讨了B2C电子商务中消费者认知到的风险来源结构,以及这些风险来源对消费者认知风险的影响。结果表明:消费者在B2C电子商务中的认知风险一部分来源于虚实界面  相似文献   
264.
The Maximum-likelihood estimator dominates the estimation of general structural equation models. Noniterative, equation-by-equation estimators for factor analysis have received some attention, but little has been done on such estimators for latent variable equations. I propose an alternative 2SLS estimator of the parameters in LISREL type models and contrast it with the existing ones. The new 2SLS estimator allows observed and latent variables to originate from nonnormal distributions, is consistent, has a known asymptotic covariance matrix, and is estimable with standard statistical software. Diagnostics for evaluating instrumental variables are described. An empirical example illustrates the estimator. I gratefully acknowledge support for this research from the Sociology Program of the National Science Foundation (SES-9121564) and the Center for Advanced Study in the Behavioral Sciences, Stanford, California. This paper was presented at the Interdisciplinary Consortium for Statistical Applications at Indiana University at Bloomington (March 2, 1994) and at the RMD Conference on Causal Modeling at Purdue University, West Lafayette, Indiana (March 3-5, 1994).  相似文献   
265.
Gert Storms 《Psychometrika》1995,60(2):247-258
A Monte Carlo study was conducted to investigate the robustness of the assumed error distribution in maximum likelihood estimation models for multidimensional scaling. Data sets generated according to the lognormal, the normal, and the rectangular distribution were analysed with the log-normal error model in Ramsay's MULTISCALE program package. The results show that violations of the assumed error distribution have virtually no effect on the estimated distance parameters. In a comparison among several dimensionality tests, the corrected version of thex 2 test, as proposed by Ramsay, yielded the best results, and turned out to be quite robust against violations of the error model.  相似文献   
266.
It is demonstrated in this paper that two major tests for 2 × 2 talbes are highly related from a Bayesian perspective. Although it is well-known that Fisher's exact and Pearson's chi-square tests are asymptotically equivalent, the present analysis shows that a formal similarity also exists in small samples. The key assumption that leads to the resemblance is the presence of a continuous parameter measuring association. In particular, it is shown that Pearson's probability can be obtained by integrating a two-moment approximation to the posterior distribution of the log-odds ratio. Furthermore, Pearson's chi-square test gave an excellent approximation to the actual Bayes probability in all 2×2 tables examined, except for those with extremely disproportionate marginal frequencies.  相似文献   
267.
Linguistic coding by deaf children in relation to beginning reading success   总被引:4,自引:0,他引:4  
The coding of printed letters in a task of consonant recall was examined in relation to the level of success of prelingually and profoundly deaf children (median age 8.75 years) in beginning reading. As determined by recall errors, the deaf children who were classified as good readers appeared to use both speech and fingerspelling (manual) codes in short-term retention of printed letters. In contrast, deaf children classified as poor readers did not show influence of either of these linguistically based codes in recall. Thus, the success of deaf children in beginning reading, like that of hearing children, appears to be related to the ability to establish and make use of linguistically recoded representations of the language. Neither group showed evidence of dependence on visual cues for recall.  相似文献   
268.
The numerous mechanisms of behavior change in infant development are sometimes difficult to distinguish. Although it is agreed that elicitation and reinforcement both influence infant learning, the distinction between these two learning mechanisms was clarified in response to K. Bloom's (1984, Journal of Experimental Child Psychology, 38, 93-102) commentary. The theoretical and methodological assumptions of an functional analysis of infant behavior were made explicit in the context of the C. L. Poulson study (1983, Journal of Experimental Child Psychology, 36, 471-489). The rationale for the use of DRO schedules to control for elicitation effects of continuous reinforcement and the inadequacy of noncontingent schedules for this purpose were also discussed.  相似文献   
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