scholarly journals A Simpler Proof of the Negative Association Property for Absolute Values of Measures Tied to Generalized Orlicz Balls

2009 ◽  
Vol 57 (1) ◽  
pp. 41-56 ◽  
Author(s):  
Jakub Onufry Wojtaszczyk
2008 ◽  
Vol 17 (3) ◽  
pp. 423-435 ◽  
Author(s):  
CHARLES SEMPLE ◽  
DOMINIC WELSH

The following two conjectures arose in the work of Grimmett and Winkler, and Pemantle: the uniformly random forest F and the uniformly random connected subgraph C of a finite graph G have the edge-negative association property. In other words, for all distinct edges e and f of G, the probability that F (respectively, C) contains e conditioned on containing f is less than or equal to the probability that F (respectively, C) contains e. Grimmett and Winkler showed that the first conjecture is true for all simple graphs on 8 vertices and all graphs on 9 vertices with at most 18 edges. In this paper, we describe an infinite, nontrivial class of graphs and matroids for which a generalized version of both conjectures holds.


2019 ◽  
Vol 56 (01) ◽  
pp. 139-152 ◽  
Author(s):  
Günter Last ◽  
Ryszard Szekli

AbstractWe study negative association for mixed sampled point processes and show that negative association holds for such processes if a random number of their points fulfils the ultra log-concave (ULC) property. We connect the negative association property of point processes with directionally convex dependence ordering, and show some consequences of this property for mixed sampled and determinantal point processes. Some applications illustrate the general theory.


2008 ◽  
Vol 17 (4) ◽  
pp. 511-518 ◽  
Author(s):  
CLIFFORD C. COCKS

Semple and Welsh [5] introduced the concept of correlated matroids, which relate to conjectures by Grimmett and Winkler [2], and Pemantle [4], respectively, that the uniformly random forest and the uniformly random connected subgraph of a finite graph have the edge-negative-association property. In this paper, we extend results of Semple and Welsh, and show that the Grimmett and Winkler, and Pemantle conjectures are equivalent to statements about correlated graphic matroids. We also answer some open questions raised in [5] regarding correlated matroids, and in particular show that the 2-sum of correlated matroids is correlated.


GeroPsych ◽  
2019 ◽  
Vol 32 (3) ◽  
pp. 125-134
Author(s):  
Mechthild Niemann-Mirmehdi ◽  
Andreas Häusler ◽  
Paul Gellert ◽  
Johanna Nordheim

Abstract. To date, few studies have focused on perceived overprotection from the perspective of people with dementia (PwD). In the present examination, the association of perceived overprotection in PwD is examined as an autonomy-restricting factor and thus negative for their mental well-being. Cross-sectional data from the prospective DYADEM study of 82 patient/partner dyads (mean age = 74.26) were used to investigate the association between overprotection, perceived stress, depression, and quality of life (QoL). The analyses show that an overprotective contact style with PwD has a significant positive association with stress and depression, and has a negative association with QoL. The results emphasize the importance of avoiding an overprotective care style and supporting patient autonomy.


Crisis ◽  
1999 ◽  
Vol 20 (2) ◽  
pp. 59-63 ◽  
Author(s):  
Antoon A. Leenaars ◽  
David Lester

Canada's rate of suicide varies from province to province. The classical theory of suicide, which attempts to explain the social suicide rate, stems from Durkheim, who argued that low levels of social integration and regulation are associated with high rates of suicide. The present study explored whether social factors (divorce, marriage, and birth rates) do in fact predict suicide rates over time for each province (period studied: 1950-1990). The results showed a positive association between divorce rates and suicide rates, and a negative association between birth rates and suicide rates. Marriage rates showed no consistent association, an anomaly as compared to research from other nations.


Author(s):  
Virgil Zeigler-Hill ◽  
Avi Besser ◽  
Yuval Besser

Abstract. The purpose of the present study was to extend previous research concerning the negative perceptions of stuttering by considering the perceived leadership ability of targets who stuttered compared with targets who did not stutter. We were also interested in the possibility that negative perceptions of the targets (i.e., low levels of self-esteem, intelligence, dominance-based status motivation, and prestige-based status motivation) would mediate the association between stuttering and a lack of perceived leadership ability as well as the possibility that manipulating the ostensible self-esteem level of the target would further moderate these associations. The results for 838 Israeli community members revealed a negative association between stuttering and perceived leadership ability that was mediated by the perceived self-esteem level and dominance-based status motivation of the target. Further, the associations between stuttering and perceptions of leadership ability were moderated by the ostensible self-esteem level of the target. Discussion focuses on the implications of these results for understanding the negative halo that surrounds stuttering.


Author(s):  
Simerpreet Kukreja

Introduction: Cigarette smoking induces many chronic illnesses, but in developed countries it is a preventable risk factor. However, by increasing the protective protection mechanism, it may be possible to alleviate the smoke-induced damage. As smoking risk is minimised by vitamin C intake, it is recommended that smokers should take more vitamin C. This inverse correlation between both vitamin C intake and serum levels and smoking was independent of age, sex, body weight, ethnicity, and consumption of alcoholic beverages. The negative association between cigarette smoking and serum vitamin C levels continued, following further adjustment for dietary vitamin C intake. The risk of severe hypovitaminosis C, especially when not accompanied by vitamin supplementation, has been increased in smokers. These data indicate that the inverse relationship between smoking and serum vitamin C levels exists independently of dietary intake, while smoking adversely affects preferences for vitamin C rich foods. Methods: A survey method was performed, with 50 smokers (S) receiving either 500 mg of vitamin C or placebo (P) daily for 4 weeks, and 50 non-smokers receiving vitamin C without supplementation. All finished the hearing. Both groups were equal and C: 14.2 + /- 1.8 pack-years was the amount of cigarettes smoked. Concentrations of plasma vitamin C increased significantly (p < 0.005) only in the vitamin C supplement community.  Results: At SMHRC Hospital Nagpur, we examined the relationship between smoking and vitamin C status, dietary and serum vitamin C levels of 100 participants. Smokers of 20 cigarettes a day had the lowest dietary intake of vitamin C and serum levels, whereas smokers of 1-19 cigarettes a day had lower intake of vitamin C and serum levels (compared to respondents who had never smoked. This inverse correlation between vitamin C and smoking intake and serum levels was independent of age, sex, body weight, race, and consumption of alcoholic beverages. The negative association between cigarette smoking and serum vitamin C levels continued, following further adjustment for dietary vitamin C intake. In smokers, the risk of severe hypo-vitaminosis C, particularly when not accompanied by vitamin supplementation, has increased. Conclusion: These data indicate that the inverse relationship between smoking and serum vitamin C levels exists independently of dietary intake, while smoking adversely affects preferences for vitamin C rich foods. A balanced diet for smokers will obtain a hearty recommendation at this time, but guidelines should remain cautious about high-dose nutrition supplements. Keywords: Chain Smoker, Vitamin C, hypo-vitaminosis C and cigarette.


2019 ◽  
Author(s):  
Federico Morelli ◽  
Yanina

ContextThe negative association between elevation and species richness is a well-recognized pattern in macro-ecology. ObjectivesThe aim of this study was to investigate changes in functional evenness of breeding bird communities along an elevation gradient in Europe. MethodsUsing the bird data from the EBCC Atlas of European Breeding Birds we estimated an index of functional evenness which can be assumed as a measure of the potential resilience of communities.ResultsOur findings confirm the existence of a negative association between elevation and bird species richness in all European eco regions. However, we also explored a novel aspect of this relationship, important for conservation: Our findings provide evidence at large spatial scale of a negative association between the functional evenness (potential community resilience) and elevation, independent of the eco region. We also found that the Natura2000 protected areas covers the territory most in need of protection, those characterized by bird communities with low potential resilience, in hilly and mountainous areas.ConclusionsThese results draw attention to European areas occupied by bird communities characterized by a potential lower capacity to respond to strong ecological changes, and, therefore, potentially more exposed to risks for conservation.


Sign in / Sign up

Export Citation Format

Share Document