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211.
William J. Chopik Jeewon Oh Sneha R. Challa Hannah L. Hua Julia M. Maahs Jacqui Smith 《Personal Relationships》2023,30(3):913-938
Childhood experiences and impressions are important for individuals' health and well-being—they often set the stage for how people approach relationships across the lifespan and how they make sense of their relational worlds. However, impressions of these experiences are likely not static and can change over time, even years after these experiences happened. The current study examined how impressions of parental relationships in childhood changed over time, and predictors of these changes, among middle-aged and older adults followed over a 4-year period (N = 2692; Mage = 66.67, SD = 9.15; 64.1% women). Childhood impressions of parental care were mostly stable over time, with 53.5%–65.0% of participants reporting consistent impressions. Becoming divorced/separated as an adult was associated with more negative impressions about relationships with fathers in the past. Having a mother pass away was associated with more positive impressions of mothers' caregiving when participants were children. Higher depressive symptoms at follow-up were associated with darker perceptions of the past—more negative impressions of mothers and fathers as caregivers. The current study is one of the most comprehensive studies of late-life changes in childhood impressions to date, suggesting future directions for studying the organization of relational experiences and recollection over time. 相似文献
212.
213.
Five domestic hens were exposed to a delayed matching-to-sample task. Conditions 1, 5, and 8 were variable-delay conditions in which five delays (0.25, 1, 2, 4, and 8 s) from the red or green sample to the presentation of the red and green comparison stimuli were presented a number of times during each session. In the fixed-delay condition (Condition 3), each delay was presented for 15 sessions under a Latin square design across birds. When improvements in accuracy across the variable-delay conditions are taken into account, the data were similar under both the variable and fixed delays. In Conditions 2, 4, 6, and 7 sample-reinforcer intervals were held at 8, 8, 4, and 2 s, respectively, while sample-choice intervals were varied within these during each session. With increasing sample-reinforcer interval, both initial discriminability (i.e., with sample-choice delay = 0) and rate of decrement in discriminability decreased. Although the former would be predicted if accuracy depends of the average sample-reinforcer interval, the latter would not. These data show that increasing the sample-choice interval had less effect on matching accuracy than increasing the sample-reinforcer interval did. 相似文献
214.
Maximum likelihood estimation is computationally infeasible for latent variable models involving multivariate categorical responses, in particular for the LISCOMP model. A three-stage generalized least squares approach introduced by Muthén (1983, 1984) can experience problems of instability, bias, non-convergence, and non-positive definiteness of weight matrices in situations of low prevalence, small sample size and large numbers of observed indicator variables. We propose a quadratic estimating equations approach that only requires specification of the first two moments. By performing simultaneous estimation of parameters, this method does not encounter the problems mentioned above and experiences gains in efficiency. Methods are compared through a numerical study and an application to a study of life-events and neurotic illness.The authors would like to thank Bengt Muthén for many helpful discussions and Scott Henderson for generously providing the Canberra data set. This work was supported in part by grant number GM49909 of the National Institutes of Health. 相似文献
215.
Should knowledge entail belief? 总被引:4,自引:0,他引:4
Joseph Y. Halpern 《Journal of Philosophical Logic》1996,25(5):483-494
The appropriateness of S5 as a logic of knowledge has been attacked at some length in the philosophical literature. Here one particular attack based on the interplay between knowledge and belief is considered: Suppose that knowledge satisfies S5, belief satisfies KD45, and both the entailment property (knowledge implies belief) and positive certainty (if the agent believes something, she believes she knows it) hold. Then it can be shown that belief reduces to knowledge: it is impossible to have false beliefs. While the entialment property has typically been viewed as perhaps the least controversial of these assumptions, an argument is presented that it can plausibly be viewed as the culprit. More precisely, it is shown that this attack fails if we weaken the entailment property so that it applies only to objective (nonmodal) formulas, rather than to arbitrary formulas. Since the standard arguments in favor of the entailment property are typically given only for objective formulas, this observation suggests that care must be taken in applying intuitions that seem reasonable in the case of objective formulas to arbitrary formulas.Research sponsored in part by the Air Force office of Scientific Research (AFSC), under Contract F49620-91-C-0080. The United States Government is authorized to reproduce and distribute reprints for governmental purposes. 相似文献
216.
We propose a method to reduce many categorical variables to one variable withk categories, or stated otherwise, to classifyn objects intok groups. Objects are measured on a set of nominal, ordinal or numerical variables or any mix of these, and they are represented asn points inp-dimensional Euclidean space. Starting from homogeneity analysis, also called multiple correspondence analysis, the essential feature of our approach is that these object points are restricted to lie at only one ofk locations. It follows that thesek locations must be equal to the centroids of all objects belonging to the same group, which corresponds to a sum of squared distances clustering criterion. The problem is not only to estimate the group allocation, but also to obtain an optimal transformation of the data matrix. An alternating least squares algorithm and an example are given.The authors thank Eveline Kroezen and Teije Euverman for their comments on a previous draft of this paper. 相似文献
217.
短时距估计中的标量特性 总被引:1,自引:1,他引:0
使用单任务研究程序,采用预期式研究范式和再现时距的研究方法,从心理物理学的视角,通过三个实验系统地考查了人类短时距估计的标量特性、变异源、时距估计中的转换点和韦伯函数的形态等问题。结果表明,刺激物的运动、变化、速度和物理时距是被试进行短时距估计的重要变异源;被试在实验中表现出高估较短时距和低估较长时距的倾向,时距估计的转换点为11.1s;计时过程中得到的韦伯函数是个分段连续函数, 韦伯函数的拐点有两个12s和21s,这两点与本研究得到的时距估计转换点具有部分一致性 相似文献
218.
执行功能可分离性及与年龄关系的潜变量分析 总被引:17,自引:2,他引:15
应用潜变量分析研究抑制优势反应、记忆刷新和注意转换三种执行功能的可分离性,以及与年龄的关系。被试为18~85岁的健康成年人142名,完成九项执行功能任务。结果显示:本研究设计的九项执行功能任务有较好的信度;验证性因子分析显示,九项任务与对应执行功能间的因子负荷较高(汇聚性效度好),而不同执行功能间的相关较低(鉴别性效度好);在此基础上建立了三种执行功能及其与年龄关系的潜变量分析模型。研究结果表明,执行系统不是单一的认知结构,可以分离为若干相对独立的执行加工过程。 相似文献
219.
Adults apply ownership not only to objects but also to ideas. But do people come to apply principles of ownership to ideas because of being taught about intellectual property and copyrights? Here, we investigate whether children apply rules from physical property ownership to ideas. Studies 1a and 1b show that children (6–8 years old) determine ownership of both objects and ideas based on who first establishes possession of the object or idea. Study 2 shows that children use another principle of object ownership, control of permission—an ability to restrict others’ access to the entity in question—to determine idea ownership. In Study 3 , we replicate these findings with different idea types. In Study 4 , we determine that children will not apply ownership to every entity, demonstrating that they do not apply ownership to a common word. Taken together, these results suggest that, like adults, children as young as 6 years old apply rules from ownership not only to objects but to ideas as well. 相似文献
220.
Thea Ionescu 《New Ideas in Psychology》2012,30(2):190-200
Cognitive flexibility is an important characteristic that helps humans pursue complex tasks, such as multitasking and finding novel, adaptable solutions to changing demands. Yet it is still a poorly understood construct. After briefly reviewing several investigations of this construct in cognitive science, I propose a unified account that considers cognitive flexibility a property of the cognitive system, rather than a cognitive skill. The emergence of cognitive flexibility is dependent on two kinds of interactions: the interaction of several cognitive mechanisms, and the interaction of sensorimotor mechanisms, cognition, and context in developmental time. The quest for a comprehensive and unified account of cognitive flexibility is highly justified given its potential usefulness in fostering efficient problem solving and creativity. 相似文献