排序方式: 共有11条查询结果,搜索用时 15 毫秒
1.
Aviv A Shay J Christensen K Wright W 《Science of aging knowledge environment : SAGE KE》2005,2005(23):pe16
In this Perspective, we focus on the greater longevity of women as compared with men. We propose that, like aging itself, the longevity gender gap is exceedingly complex and argue that it may arise from sex-related hormonal differences and from somatic cell selection that favors cells more resistant to the ravages of time. We discuss the interplay of these factors with telomere biology and oxidative stress and suggest that an explanation for the longevity gender gap may arise from a better understanding of the differences in telomere dynamics between men and women. 相似文献
2.
Temporary price reductions (sales) are common for many goods and naturally result in large increases in the quantity sold. Demand estimation based on temporary price reductions may mismeasure the long‐run responsiveness to prices. In this paper we quantify the extent of the problem and assess its economic implications. We structurally estimate a dynamic model of consumer choice using two years of scanner data on the purchasing behavior of a panel of households. The results suggest that static demand estimates, which neglect dynamics, (i) overestimate own‐price elasticities by 30 percent, (ii) underestimate cross‐price elasticities by up to a factor of 5, and (iii) overestimate the substitution to the no‐purchase or outside option by over 200 percent. This suggests that policy analysis based on static elasticity estimates will underestimate price–cost margins and underpredict the effects of mergers. 相似文献
3.
In describing the processes of organizations as political acts, we are not making a moral judgment; we simply are making an observation about a process. Bacharach and Lawler, 1980, p. 2.This study focuses on the ways a perceived political climate influences engagement in political behavior during a national election period. By using social cognitive theory as a way to predict behavior in organizations, we study how managers' engagement in political behavior is shaped. A qualitative research methodology was used. Sixteen interviews with managers were conducted in various local authorities during the 2015 election campaign for Israel's parliament. Participants perceived an intensification of political climate during the pre-election period, which they attributed to a significant connection between electoral and intraorganizational politics. Additionally, a perceived organizational political climate intensifies engagement in a range of political behaviors throughout an organization and is connected with an administrative role. The findings suggest that managers use “political capital” that the election period provides to influence and manipulate their organization's future and their own. 相似文献
4.
Ossi Pesämaa Aviv Shoham Joakim Wincent Ayalla A. Ruvio 《Journal of Engineering and Technology Management》2013,30(2):169-187
Relying on organizational innovativeness for long-term growth and profitability can be difficult, time consuming, and expensive. In the context of service delivery of 395 strategic business units (SBU) in Israel's healthcare industry, this paper examines the role of a learning-orientation as a moderator in an integrative model of organizational innovativeness. We find moderation of the impacts of risk-taking, creativity, competitor benchmarking orientation, and environmental opportunities on innovativeness. Moreover, we find the influence on performance pronounced for high learning-oriented SBUs. The paper shows that learning orientation should be considered for understanding effective innovativeness work for competitive service delivery. 相似文献
5.
Aviv A 《Science of aging knowledge environment : SAGE KE》2004,2004(51):pe43
Can telomere dynamics, defined by telomere length and attrition rate, provide information about the biology of human aging above and beyond that provided by chronological age? Accruing data suggest that it can. White blood cells (WBCs) have been used as the primary model in attempts to decipher links between aging, aging-related disorders, and telomere dynamics in humans. The WBC model may be appropriate in clinical settings, provided that we fully appreciate its drawbacks and limitations. On the basis of WBC telomere data, it is evident that age-adjusted telomere length is highly variable, highly heritable, longer in women than men, and shorter in people who harbor a host of age-related disorders, whose common denominators may prove to be increased oxidative stress and inflammation. It appears that shorter age-adjusted WBC telomere length augurs a greater risk of morbidity and premature mortality in the elderly. However, it is unsettled whether human telomere dynamics is only a proxy for fundamental mechanisms that govern the course of aging or a key determinant in its progression. 相似文献
6.
We demonstrate that winner selection in two prominent proportional representation voting systems is a computationally intractable
problem—implying that these systems are impractical when the assembly is large. On a different note, in settings where the
size of the assembly is constant, we show that the problem can be solved in polynomial time. 相似文献
7.
Aviv Nevo John L. Turner Jonathan W. Williams 《Econometrica : journal of the Econometric Society》2016,84(2):411-443
We estimate demand for residential broadband using high‐frequency data from subscribers facing a three‐part tariff. The three‐part tariff makes data usage during the billing cycle a dynamic problem, thus generating variation in the (shadow) price of usage. We provide evidence that subscribers respond to this variation, and we use their dynamic decisions to estimate a flexible distribution of willingness to pay for different plan characteristics. Using the estimates, we simulate demand under alternative pricing and find that usage‐based pricing eliminates low‐value traffic. Furthermore, we show that the costs associated with investment in fiber‐optic networks are likely recoverable in some markets, but that there is a large gap between social and private incentives to invest. 相似文献
8.
Aviv Nevo 《Econometrica : journal of the Econometric Society》2001,69(2):307-342
The ready‐to‐eat cereal industry is characterized by high concentration, high price‐cost margins, large advertising‐to‐sales ratios, and numerous introductions of new products. Previous researchers have concluded that the ready‐to‐eat cereal industry is a classic example of an industry with nearly collusive pricing behavior and intense nonprice competition. This paper empirically examines this conclusion. In particular, I estimate price‐cost margins, but more importantly I am able empirically to separate these margins into three sources: (i) that which is due to product differentiation; (ii) that which is due to multi‐product firm pricing; and (iii) that due to potential price collusion. The results suggest that given the demand for different brands of cereal, the first two effects explain most of the observed price‐cost margins. I conclude that prices in the industry are consistent with noncollusive pricing behavior, despite the high price‐cost margins. Leading firms are able to maintain a portfolio of differentiated products and influence the perceived product quality. It is these two factors that lead to high price‐cost margins. 相似文献
9.
Yossi Aviv Andrei Bazhanov Yuri Levin Mikhail Nediak 《Production and Operations Management》2017,26(11):2107-2121
Legal studies usually treat a policy of a manufacturer or retailer as socially harmful if it reduces product output and increases the price. We consider a two‐period model where the first‐period price is fixed and resellers endogenously decide to use meet‐the‐competition clause with a most‐favored‐customer clause (MFC) to counteract strategic customer behavior. As a result of MFC, the second‐period (reduced) price increases and resellers’ inventories decrease. However, customer surplus may increase and aggregate welfare increases in the majority of market situations. MFC can mitigate the losses in welfare and resellers’ profits due to strategic customers. Moreover, under reseller competition, MFC may even lead to higher levels of these values than with myopic customers, that is, to gain from increased strategic behavior. With growing competition, benefits or losses from MFC can be higher than losses from strategic customer behavior. 相似文献
10.
The Symbolic Type Revisited: Semiotics in Practice and the Reformation of the Israeli Commemorative Context 下载免费PDF全文
Revisiting Grathoff's theory of symbolic type (ST), we examine the personal evolution and commemorative work of Tsipi Kichler, a cultural entrepreneur and founder of an alternative Israeli Holocaust museum/geriatric center. As hybrid product of Israeli social cleavages, Kichler exteriorizes her paradoxical vision in the museum aiming to reform Holocaust‐related discourse and practice. Early biographical positioning and resultant contradictions become translated into resistant commemorative performance where serious humor deconstructs the binaries of life/death and past/present. We consider the implications of the ST's self‐referential closure to interaction, and the transformative potential of the alignment of cultural entrepreneurs' personal memory with collective memory. 相似文献