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1.
Two ordinal consequences are drawn from the linear multiple-factor analysis model. First, the numberR(s, d) of distinct ways in whichs subjects can be ranked by linear functions ofd factors is limited by the recursive expressionR(s, d)=R(s?1,d)+(s?1)R(s?1,d?1). Second, every setS ofd+2 subjects can be separated into two subsetsS* andS ? S* such that no linear function ofd variables can rank allS* over allS ? S*, and vice versa. When these results are applied to the hypothetical data of Thurstone's “box problem,” three independent parameters are found. Relations to Thurstone's suggestion for a non-correlational factor analysis are discussed.  相似文献   

2.
LetN. be the set of all natural numbers (except zero), and letD n * = {kNk|n} ∪ {0} wherek¦n if and only ifn=k.x f or somex∈N. Then, an ordered setD n * = 〈D n * , ? n , wherex? ny iffx¦y for anyx, y∈D n * , can easily be seen to be a pseudo-boolean algebra. In [5], V.A. Jankov has proved that the class of algebras {D n * n∈B}, whereB =,{kN∶ ? \(\mathop \exists \limits_{n \in N} \) (n > 1 ≧n 2 k)is finitely axiomatizable. The present paper aims at showing that the class of all algebras {D n * n∈B} is also finitely axiomatizable. First, we prove that an intermediate logic defined as follows: $$LD = Cn(INT \cup \{ p_3 \vee [p_3 \to (p_1 \to p_2 ) \vee (p_2 \to p_1 )]\} )$$ finitely approximatizable. Then, defining, after Kripke, a model as a non-empty ordered setH = 〈K, ?〉, and making use of the set of formulas true in this model, we show that any finite strongly compact pseudo-boolean algebra ? is identical with. the set of formulas true in the Kripke modelH B = 〈P(?), ?〉 (whereP(?) stands for the family of all prime filters in the algebra ?). Furthermore, the concept of a structure of divisors is defined, and the structure is shown to beH D n * = 〈P (D n * ), ?〉for anyn∈N. Finally, it is proved that for any strongly compact pseudo-boolean algebraU satisfying the axiomp 3∨ [p 3→(p1→p2)∨(p2→p1)] there is a structure of divisorsD * n such that it is possible to define a strong homomorphism froomiH D n * ontoH D U . Exploiting, among others, this property, it turns out to be relatively easy to show that \(LD = \mathop \cap \limits_{n \in N} E(\mathfrak{D}_n^* )\) .  相似文献   

3.
Tversky, Rinott, and Newman (Journal of Mathematical Psychology, 1983, 27, 000) examine the asymptotic behavior of a measure of the centrality of the nearest neighbor relation. The applicability of their conclusions when the number of dimensions (d) and the number of points (n) take on the small-to-moderate values commonly encountered in the analysis of proximity data is investigated. The results suggest that convergence is fast when n is large relative to d and slow when d is large relative to n.  相似文献   

4.
In connection with multidimensional scaling, representations have been considered of the form abDcd?(f(a), f(b)) ≦ ?(f(c), f(d)), for all a, b, c, dA, where A is a nonvoid finite set, D is a four-place relation on A, f is a function from A into Euclidean n-space, Rn, and ? is a metric in Rn. For particular metrics there exist finite universal axiomatizations which are necessary and sufficient for the above representation. On the other hand, it is known that no such axiomatizations can be given for either the supremum metric or the ordinary Euclidean metric. Methods for showing this apply easily to the city-block metrics in R1 and R2. This article describes a computer-aided verification of a locus result which shows the impossibility of finite universal axiomatizability for the case of the city-block metric in R3. The result was obtained by dealing with 21,780 cases, each of which involved a set of 10 equations in 12 unknowns along with a related set of inequalities.  相似文献   

5.
In a famous and controversial paper, B. H. Slater has argued against the possibility of paraconsistent logics. Our reply is centred on the distinction between two aspects of the meaning of a logical constant *c* in a given logic: its operational meaning, given by the operational rules for *c* in a cut-free sequent calculus for the logic at issue, and its global meaning, specified by the sequents containing *c* which can be proved in the same calculus. Subsequently, we use the same strategy to counter Quine's meaning variance argument against deviant logics. In a nutshell, we claim that genuine rivalry between (similar) logics *L* and *L* is possible whenever each constant in *L* has the same operational meaning as its counterpart in *L* although differences in global meaning arise in at least one case.  相似文献   

6.
Psychologists would like to say that a probability distribution on {0,1}n is d-dimensional if (1) the distribution can be represented by some smooth d-dimensional latent variable model and (2) the distribution cannot be represented by any smooth d−1 dimensional model. This does not work out because for d>1, every distribution that can be represented by a smooth d-dimensional model can also be represented by a smooth one-dimensional model. A proof and discussion of some implications of this mathematical result follow.  相似文献   

7.
Cognitive Behavioral Therapy (CBT) is effective in reducing insomnia complaints, but the effects of self-help CBT have been inconsistent. The aim of this study was to determine the effectiveness of self-help for insomnia delivered in either electronic or paper-and-pencil format compared to a waiting-list. Participants kept a diary and filled out questionnaires before they were randomized into electronic (n = 216), paper-and-pencil (n = 205), or waiting-list (n = 202) groups. The intervention consisted of 6 weeks of unsupported self-help CBT, and post-tests were 4, 18, and 48 weeks after intervention. At 4-week follow-up, electronic and paper-and-pencil conditions were superior (p < .01) compared to the waiting-list condition on most daily sleep measures (Δd = 0.29–0.64), global insomnia symptoms (Δd = 0.90–1.00), depression (Δd = 0.36–0.41), and anxiety symptoms (Δd = 0.33–0.40). The electronic and paper-and-pencil groups demonstrated equal effectiveness 4 weeks after treatment (Δd = 0.00–0.22; p > .05). Effects were sustained at 48-week follow-up. This large-scale unsupported self-help study shows moderate to large effects on sleep measures that were still present after 48 weeks. Unsupported self-help CBT for insomnia therefore appears to be a promising first option in a stepped care approach.  相似文献   

8.
《Behavior Therapy》2022,53(3):440-457
Insomnia is highly prevalent among military veterans but access to cognitive-behavioral therapy for insomnia (CBT-I) is limited. Thus, this study examined the feasibility, acceptability, and potential efficacy of Insomnia Coach, a CBT-I-based, free, self-management mobile app. Fifty U.S. veterans, who were mostly male (58%) and mean age 44.5 (range = 28–55) years with moderate insomnia symptoms were randomized to Insomnia Coach (n = 25) or a wait-list control condition (n = 25) for 6 weeks. Participants completed self-report measures and sleep diaries at baseline, posttreatment, and follow-up (12 weeks postrandomization), and app participants (n = 15) completed a qualitative interview at posttreatment. Findings suggest that Insomnia Coach is feasible to use, with three quarters of participants using the app through 6 weeks and engaging with active elements. For acceptability, perceptions of Insomnia Coach were very favorable based on both self-report and qualitative interview responses. Finally, for potential efficacy, at posttreatment, a larger proportion of Insomnia Coach (28%) than wait-list control participants (4%) achieved clinically significant improvement (p = .049) and there was a significant treatment effect on daytime sleep-related impairment (d = −0.6, p = .044). Additional treatment effects emerged at follow-up for insomnia severity (d = −1.1, p = .001), sleep onset latency (d = −0.6, p = .021), global sleep quality (d = −0.9, p = .002), and depression symptoms (d = −0.8, p = .012). These findings provide preliminary evidence that among veterans with moderate insomnia symptoms, a CBT-I-based self-management app is feasible, acceptable, and promising for improving insomnia severity and other sleep-related outcomes. Given the vast unmet need for insomnia treatment in the population, Insomnia Coach may provide an easily accessible, convenient public health intervention for individuals not receiving care.  相似文献   

9.
Two auditory amplitude discrimination experiments were conducted using thesame-different experimental design. Observer bias was manipulated, in the first experiment, by varying payoff matrices and, in the second, by varying prior probabilities of signal presentation. Five levels of bias manipulation and four levels of difficulty were employed in each experiment. Each observer received all combinations of bias manipulation and difficulty, but with only one of these combinations within each block of trials. Nine indices of bias were assessed by simultaneously fitting isosensitivity and isobias functions to the data and by fitting isobias functions only. Although none of the indices tested provided an exceptionally good fit to the data, two indices stood out from the rest. These werec sd * andc i, indices with isobias contours similar in shape to those for thec index derived from theyes-no task.  相似文献   

10.
《Behavior Therapy》2023,54(2):230-246
This study aimed at evaluating the efficacy of an online CBT intervention with limited therapist contact targeting a range of posttraumatic symptoms among evacuees from the 2016 Fort McMurray wildfires.One hundred and thirty-six residents of Fort McMurray who reported either moderate PTSD symptoms (PCL-5 ≥ 23) or mild PTSD symptoms (PCL-5 ≥ 10) with moderate depression (PHQ-9 ≥ 10) or subthreshold insomnia symptoms (ISI ≥ 8) were randomized either to a treatment (n = 69) or a waitlist condition (n = 67). Participants were on average 45 years old, and mostly identified as White (82%) and as women (76%). Primary outcomes were PTSD, depression, and insomnia symptoms. Secondary outcomes were anxiety symptoms and disability. Significant Assessment Time × Treatment Condition interactions were observed on all outcomes, indicating that access to the treatment led to a decrease in posttraumatic stress (F[1,117.04] = 12.128, p = .001; d = .519, 95% CI = .142–.895), depression (F[1,118.29] = 9.978, p = .002; d = .519, 95% CI = .141–.898) insomnia (F[1,117.60] = 4.574, p = .035; d = .512, 95% CI = .132–.892), and anxiety (F[1,119.64] = 5.465, p = .021; d = .421, 95% CI = .044–.797) symptom severity and disability (F[1,111.55] = 7.015, p = .009; d = .582, 95% CI = .200–.963). Larger effect sizes (d = 0.823–1.075) were observed in participants who completed at least half of the treatment. The RESILIENT online treatment platform was successful to provide access to specialized evidence-based mental health care after a disaster.  相似文献   

11.
《Behavior Therapy》2023,54(3):557-571
Although the efficacy of online administration of behavioral parent training (BPT) programs is well-established, such programs address a single risk factor (behavioral functioning) for school readiness difficulties (comprised of academics, cognitive skills, and social, emotional, and behavioral functioning). The current study aims to examine the feasibility, acceptability, and efficacy of a telemedicine delivery of the School Readiness Parenting Program (SRPP), an integrative adaptation of PCIT designed to address the behavioral and academic domains of school readiness. The present study takes the first step towards validating an online administration of the SRPP as a treatment for early childhood disruptive behavior. Data were collected for 64 children ages 2–6 years (Mage = 4.63, SD = 0.86; 78.1% Hispanic/Latinx) and their families, who received either in-person administration of time-limited PCIT (PCIT-TL; n=30) or online administration of SRPP (n=34). A series of repeated measures ANOVAS were conducted to examine within and between group effects. Results revealed that both SRPP and PCIT-TL significantly reduced inattention (d’s = −0.54 to −0.88), aggression (d’s = −0.55 to −1.06), and behavioral symptomology (d’s = −0.55 to −0.85) and produced significant gains in parental skills (d’s = −1.47 to 2.99). Notably, online SRPP demonstrated greater improvement in positive parental verbalization, whereas PCIT-TL demonstrated greater reductions in parental stress. Overall, findings support the utility of online SRPP for addressing behavioral school readiness concerns.  相似文献   

12.
Abstract

The dependence of the normal-state resistivity, resistive superconducting transition (T c, ΔT c), and of the upper critical-field slope (dH c2/dT|T=Tc) on density has been investigated for several YBa2Cu3O9-x(x?2.1) samples. The resistivity decreases rapidly with increasing density, whereas T c and ΔT c are rather insensitive to a change in density. dH c2/dT|Tc depends sensitively on the preparation conditions. The implications of these results both for the evaluation of the parameters relevant to the understanding of the nature of superconductivity and for the technological applications of granular superconductors are briefly discussed.  相似文献   

13.
Shieh (2013) discussed in detail δ*, a proposed standardized effect size measure for the two-independent-groups design with heteroscedasticity. Shieh focused on inference—notably, the large challenge of calculating confidence intervals for δ*. I contend, however, that the standardizer chosen for δ*, meaning the units in which it is expressed, is appropriate for inference but causes δ* to be inconsistent with conventional Cohen’s d. In addition, δ* depends on the relative sample sizes in the particular experiment and, thus, lacks the generality that is highly desirable if a standardized effect size is to be readily interpretable and also usable in meta-analysis. In the case of heteroscedasticity, I suggest that researchers should choose as standardizer for Cohen’s δ the best available estimate of the SD of an appropriate population, usually the control population, in preference to δ* as discussed by Shieh.  相似文献   

14.
Internet-delivered treatment is effective for insomnia, but little is known about the beneficial effects of support. The aim of the current study was to investigate the additional effects of low-intensity support to an internet-delivered treatment for insomnia. Two hundred and sixty-two participants were randomized to an internet-delivered intervention for insomnia with (n = 129) or without support (n = 133). All participants received an internet-delivered cognitive behavioral treatment for insomnia. In addition, the participants in the support condition received weekly emails. Assessments were at baseline, post-treatment, and 6-month follow-up. Both groups effectively ameliorated insomnia complaints. Adding support led to significantly higher effects on most sleep measures (d = 0.3–0.5; p < 0.05), self-reported insomnia severity (d = 0.4; p < 0.001), anxiety, and depressive symptoms (d = 0.4; p < 0.01). At the 6-month follow-up, these effects remained significant for sleep efficiency, sleep onset latency, insomnia symptoms, and depressive symptoms (d = 0.3–0.5; p < 0.05). Providing support significantly enhances the benefits of internet-delivered treatment for insomnia on several variables. It appears that motivational feedback increases the effect of the intervention and encourages more participants to complete the intervention, which in turn improves its effectiveness.  相似文献   

15.
Peter C. Fishburn 《Synthese》1970,21(2):204-221
a–b* c–d is taken to mean that your degree of preference for a over b is less than your degree of preference for c over d. Various properties of the strength-of-preference comparison relation * are examined along with properties of simple preferences defined from *. The investigation recognizes an individual's limited ability to make precise judgments. Several utility theorems relating a–b * c–d to u(a)–u(b) are included.  相似文献   

16.
Research on the improvement of elementary school mathematics has shown that computer-based training of number sense (e.g., processing magnitudes or locating numbers on the number line) can lead to substantial achievement gains in arithmetic skills. Recent studies, however, have highlighted that training domain-general cognitive abilities (e.g., working memory [WM]) may also improve mathematical achievement. This study addressed the question of whether a training of domain-specific number sense skills or domain-general WM abilities is more appropriate for improving mathematical abilities in elementary school. Fifty-nine children (Mage = 9 years, 32 girls and 27 boys) received either a computer-based, adaptive training of number sense (n = 20), WM skills (n = 19), or served as a control group (n = 20). The training duration was 20 min per day for 15 days. Before and after training, we measured mathematical ability using a curriculum-based math test, as well as spatial WM. For both training groups, we observed substantial increases in the math posttest compared to the control group (d = .54 for number sense skills training, d = .57 for WM training, respectively). Whereas the number sense group showed significant gains in arithmetical skills, the WM training group exhibited marginally significant gains in word problem solving. However, no training group showed significant posttest gains on the spatial WM task. Results indicate that a short training of either domain-specific or domain-general skills may result in reliable short-term training gains in math performance, although no stable training effects were found in the spatial WM task.  相似文献   

17.
The mechanical behaviour of polycrystalline hexagonal close-packed cobalt was investigated over a large range of grain size d in order to examine the occurrence of size effects. Crystallographic texture and amount of face centred cubic allotropic phase were maintained unchanged thanks to appropriate heat treatment procedures. The Hall–Petch (HP) relation exhibits two distinct behaviours from the very beginning of plastic strain levels. The conventional HP law is fulfilled for a number of grains across the thickness t higher than a critical value (t/d)c = 14. For t/d lower than (t/d)c, a multicrystalline regime is evidenced highlighting a strong reduction in flow stress. The high value of (t/d)c is related to the low-stacking fault energy of cobalt in the basal plane. The size effect is predominant in the first work hardening stage where slip mechanisms and stacking faults predominate. In the second stage, driven by mechanical twinning processes, this effect is less sensitive. Finally, the size effect could also affect the end of the elastic stage, in link with nonlinear elasticity mechanisms.  相似文献   

18.
A visual world experiment examined the time course for pragmatic inferences derived from visual context and contrastive intonation contours. We used the construction It looks like an X pronounced with either (a) a H* pitch accent on the final noun and a low boundary tone, or (b) a contrastive L + H* pitch accent and a rising boundary tone, a contour that can support contrastive inference (e.g., It LOOKSL+H*like a zebraL-H%… (but it is not)). When the visual display contained a single related set of contrasting pictures (e.g. a zebra vs. a zebra-like animal), effects of LOOKSL+H* emerged prior to the processing of phonemic information from the target noun. The results indicate that the prosodic processing is incremental and guided by contextually-supported expectations. Additional analyses ruled out explanations based on context-independent heuristics that might substitute for online computation of contrast.  相似文献   

19.
BackgroundExercise interventions are efficacious in reducing disorder-specific symptoms in various mental disorders. However, little is known about long-term transdiagnostic efficacy of exercise across heterogenous mental disorders and the potential mechanisms underlying treatment effects.MethodsPhysically inactive outpatients, with depressive disorders, anxiety disorders, insomnia or attention deficit hyperactivity disorder were randomized to a standardized 12-week exercise intervention, combining moderate exercise with behavior change techniques (BCTs) (n = 38), or a passive control group (n = 36). Primary outcome was global symptom severity (Symptom Checklist-90, SCL-90-R) and secondary outcomes were self-reported exercise (Physical Activity, Exercise, and Sport Questionnaire), exercise-specific affect regulation (Physical Activity-related Health Competence Questionnaire) and depression (SCL-90-R) assessed at baseline (T1), post-treatment (T2) and one year after post-treatment (T3). Intention-to-treat analyses were conducted using linear mixed models and structural equations modeling.ResultsFrom T1 to T3, the intervention group significantly improved on global symptom severity (d = −0.43, p = .031), depression among a depressed subsample (d = −0.62, p = .014), exercise (d = 0.45, p = .011) and exercise-specific affect regulation (d = 0.44, p = .028) relative to the control group. The intervention group was more likely to reveal clinically significant changes from T1 to T3 (p = .033). Increases in exercise-specific affect regulation mediated intervention effects on global symptom severity (ß = −0.28, p = .037) and clinically significant changes (ß = −0.24, p = .042).ConclusionsThe exercise intervention showed long-term efficacy among a diagnostically heterogeneous outpatient sample and led to long-lasting exercise behavior change. Long-term increases in exercise-specific affect regulation within exercise interventions seem to be essential for long-lasting symptom reduction.  相似文献   

20.
ObjectiveTo assess the relationship between session-by-session putative mediators and treatment outcomes in traditional cognitive behavioral therapy (CBT) and acceptance and commitment therapy (ACT) for mixed anxiety disorders.MethodSession-by-session changes in anxiety sensitivity and cognitive defusion were assessed in 67 adult outpatients randomized to CBT (n = 35) or ACT (n = 32) for a DSM-IV anxiety disorder.ResultsMultilevel mediation analyses revealed significant changes in the proposed mediators during both treatments (p < .001, d = .90–1.93), with ACT showing borderline greater improvements than CBT in cognitive defusion (p = .05, d = .82). Anxiety sensitivity and cognitive defusion both significantly mediated post-treatment worry; cognitive defusion more strongly predicted worry reductions in CBT than in ACT. In addition, cognitive defusion significantly mediated quality of life, behavioral avoidance, and (secondary) depression outcomes across both CBT and ACT (p < .05, R2 change = .06–.13), whereas anxiety sensitivity did not significantly mediate other outcomes.ConclusionsCognitive defusion represents an important source of therapeutic change across both CBT and ACT. The data offered little evidence for substantially distinct treatment-related mediation pathways.  相似文献   

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