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951.
The purpose of this study was to provide a more comprehensive understanding of the relation between early parent‐child interactions and subsequent behavior problems and how certain cognitive processes mediate this relation. Specifically, this study investigated whether attention, inhibition, and planning skills mediate the relation between attachment security and behavior problems. Data were collected as part of the National Institute of Child Health and Development‐Study of Early Child Care and Youth Development when children (N = 1004) were between 36 months and the third grade. Results from structural equation models indicated that sustained attention mediated the relation between disorganized attachment and social problems. Planning mediated the relation between disorganized attachment and subsequent thought problems, attention problems, and delinquent behavior. Avoidant, ambivalent, and disorganized attachment directly predicted several behavior problems. Implications for theory and future research are discussed. 相似文献
952.
Demographic ageing is a challenge for many countries. Even though Turkey has a relatively younger demographic composition, the proportion of the older people (65+) within the population is rapidly increasing. Within this framework, older people are becoming more important clients for both social work students and social workers in Turkey. This study aims to reveal the attitudes of social work students towards older people and determine the various factors that affect their views on older persons. In the scope of the project, Kogan's Attitude Towards Old People Scale was applied to 419 social work undergraduate students at a university located in Central Anatolia. The findings showed that social work students scored a mean of 130.96 and they generally had positive attitudes towards older people. The correlation between year of study, gender and age was not statistically significant. However, having lived mostly in urban areas was positively correlated with the mean Kogan scores and this finding was found to be statistically significant. Exposure to personal contact with older people at both the personal and professional levels was influential in shaping attitudes about the older people. 相似文献
953.
954.
Ma. Sofia Criselda A. Poblador 《统计学通讯:模拟与计算》2016,45(9):3373-3393
We propose to use AR-Sieve Bootstrap in the construction of a control chart of an autocorrelated process influenced by multiple exogenous inputs. The control charts are compared with Exponentially Weighted Moving Average (EWMA) control chart through a simulation study. AR-Sieve bootstrap control limits are narrower than EWMA control limits. While the proposed method yields a higher rate of false alarms, it is quick in detecting even minimal structural changes. 相似文献
955.
956.
Cord A. Müller 《Journal of applied statistics》2019,46(13):2338-2356
ABSTRACTAcceptance sampling plans offered by ISO 2859-1 are far from optimal under the conditions for statistical verification in modules F and F1 as prescribed by Annex II of the Measuring Instruments Directive (MID) 2014/32/EU, resulting in sample sizes that are larger than necessary. An optimised single-sampling scheme is derived, both for large lots using the binomial distribution and for finite-sized lots using the exact hypergeometric distribution, resulting in smaller sample sizes that are economically more efficient while offering the full statistical protection required by the MID. 相似文献
957.
958.
This paper discusses a novel strategy for simulating rare events and an associated Monte Carlo estimation of tail probabilities.
Our method uses a system of interacting particles and exploits a Feynman-Kac representation of that system to analyze their
fluctuations. Our precise analysis of the variance of a standard multilevel splitting algorithm reveals an opportunity for
improvement. This leads to a novel method that relies on adaptive levels and produces, in the limit of an idealized version
of the algorithm, estimates with optimal variance. The motivation for this theoretical work comes from problems occurring
in watermarking and fingerprinting of digital contents, which represents a new field of applications of rare event simulation
techniques. Some numerical results show performance close to the idealized version of our technique for these practical applications. 相似文献
959.
The disease burden of pathogens as estimated by QMRA (quantitative microbial risk assessment) and EA (epidemiological analysis) often differs considerably. This is an unsatisfactory situation for policymakers and scientists. We explored methods to obtain a unified estimate using campylobacteriosis in the Netherlands as an example, where previous work resulted in estimates of 4.9 million (QMRA) and 90,600 (EA) cases per year. Using the maximum likelihood approach and considering EA the gold standard, the QMRA model could produce the original EA estimate by adjusting mainly the dose‐infection relationship. Considering QMRA the gold standard, the EA model could produce the original QMRA estimate by adjusting mainly the probability that a gastroenteritis case is caused by Campylobacter. A joint analysis of QMRA and EA data and models assuming identical outcomes, using a frequentist or Bayesian approach (using vague priors), resulted in estimates of 102,000 or 123,000 campylobacteriosis cases per year, respectively. These were close to the original EA estimate, and this will be related to the dissimilarity in data availability. The Bayesian approach further showed that attenuating the condition of equal outcomes immediately resulted in very different estimates of the number of campylobacteriosis cases per year and that using more informative priors had little effect on the results. In conclusion, EA was dominant in estimating the burden of campylobacteriosis in the Netherlands. However, it must be noted that only statistical uncertainties were taken into account here. Taking all, usually difficult to quantify, uncertainties into account might lead to a different conclusion. 相似文献
960.
In the present paper we introduce the indicators of the fuzzy transitive congruence axiom, fuzzy direct-revelation axiom and fuzzy acyclic congruence axiom. These indicators measure the degree to which a fuzzy choice function satisfies these axioms. We use the indicators of fuzzy transitive congruence axiom and fuzzy acyclic congruence axiom to calculate the minimum degree to which the direct fuzzy revealed preference relation is the transitive and acyclic respectively. We established that (i) the degree to which the fuzzy choice function is full rational is the degree to which it satisfies fuzzy transitive congruence axiom and (ii) the degree to which the fuzzy choice function is acyclic rational is the minimum degree to which it satisfies fuzzy direct-revelation axiom and its fuzzy revealed preference is acyclic. We show that a similarity relation on the set of fuzzy choice functions preserves the indicators of fuzzy transitive congruence axiom, fuzzy direct-revelation axiom, fuzzy acyclic congruence axiom and (transitive and acyclic) rationality indicators. 相似文献