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791.
Shantanu Bhattacharya Sameer Hasija Luk N. Van Wassenhove 《Production and Operations Management》2014,23(9):1511-1521
We analyze the efficacy of different asset transfer mechanisms and provide policy recommendations for the design of humanitarian supply chains. As a part of their preparedness effort, humanitarian organizations often make decisions on resource investments ex ante because doing so allows for rapid response if an adverse event occurs. However, programs typically operate under funding constraints and donor earmarks with autonomous decision‐making authority resting with the local entities, which makes the design of efficient humanitarian supply chains a challenging problem. We formulate this problem in an agency setting with two independent aid programs, where different asset transfer mechanisms are considered and where investments in resources are of two types: primary resources that are needed for providing the aid and infrastructural investments that improve the operation of the aid program in using the primary resources. The primary resources are acquired from earmarked donations. We show that allowing aid programs the flexibility of transferring primary resources improves the efficiency of the system by yielding greater social welfare than when this flexibility does not exist. More importantly, we show that a central entity that can acquire primary resources from one program and sell them to the other program can further improve system efficiency by providing a mechanism that facilitates the transfer of primary resources and eliminates losses from gaming. This outcome is achieved without depriving the individual aid programs of their decision‐making autonomy while maintaining the constraints under which they operate. We find that outcomes with centralized resource transfer but decentralized infrastructural investments by the aid programs are the same as with a completely centralized system (where both resource transfer and infrastructural investments are centralized). 相似文献
792.
793.
The Genesis of this Special Issue came from the Board of the POMS College on Humanitarian Operations and Crisis Management (HO&CM). It was seen as a necessary initiative to define the field and examine research opportunities. This Special Issue shows that humanitarian operations pose challenges for P/OM researchers and practitioners that differ markedly from those of conventional supply chains associated with profitable enterprises. On the basis of the eight articles in this Special Issue, we have described and demonstrated the unique characteristics of the POM/HO&CM interaction. We have also identified those attributes that tend to overlap with conventional aspects of POM. In addition to wanting to be cost effective, the issue of equity fairness is pervasive in humanitarian operations, and so is the need to always base considerations on “last‐mile logistics,” that is, getting aid to those in most need. Research is essential to determine how to train researchers to scout out and map the territory of the real problems. One of the most vexing problems is the lack of robust data in the humanitarian domain which is as richly varied as the types of disasters that can occur. 相似文献
794.
N. A. Hamilton C. A. Nelson N. Stevens Heather Kitzman 《Social indicators research》2007,82(1):147-163
Although many studies have linked sleep problems with symptoms of psychopathology, fewer studies have examined the relationship
between sleep and dimensions of psychological health as well as depression. To fill this gap, 502 community residents were
surveyed about sleep habits, symptoms of anxiety and depression, as well as Ryff’s six dimensions of psychological well-being.
Using cut-offs suggested by epidemiological research, participants were classified as either optimal sleepers (those reporting
an average of 6 hours or less than 8.5 hours per night) or suboptimal sleepers (those sleeping less than 6 hours or 8.5 or
more hours per night). After controlling for demographic differences (i.e., sex, age, education, ethnicity, employment status,
marital status, presence of children), the Multivariate Analysis of Covariance (MANCOVA) suggested that optimal sleepers reported
fewer symptoms of depression, and anxiety, and reported higher levels of environmental mastery, personal growth, positive
relations with others, purpose in life, and self acceptance. Differences between optimal sleepers and non-optimal sleepers
in depressive symptoms, positive relations with others, purpose in life and self-acceptance remained significant when people
with mild to moderate symptoms of depression were eliminated from the data set. These results are consistent with a theoretical
framework that defines sleep as a resource related to stress management and self-regulation. 相似文献
795.
M. N. Barringer 《Journal of homosexuality》2020,67(9):1173-1196
ABSTRACT The cumulative alienation sexual minorities experience from American mainline religious groups may leave them feeling disillusioned and even hostile toward the religious organizations that have historically rejected them. However, research to date has not explored sexual minorities’ perceptions of religious traditions in the United States. The current study examines the variations between lesbian, gay, and bisexual adults’ (LGB) perceptions of whether religious traditions are friendly/neutral or unfriendly toward the LGBT (lesbian, gay, bisexual, and transgender) population. Using data from the Pew Research Center 2013 Survey of LGBT Adults, the author conducts separate binary logistic regression analyses examining whether four religious traditions—evangelical Protestantism, the Catholic Church, the Jewish religion, and mainline Protestantism—are generally perceived as friendly/neutral or unfriendly toward LGBT people. The findings from this study offer rare insight on sexual minorities’ perceptions of major religious traditions and illustrates that sexual minorities have a complex relationship with religion. 相似文献
796.
Summary Until now, mathematical models of parasitoid-host interactions have not incorporated the tendency for destructively host-feeding
parasitoids to partition their feeding and oviposition behaviour in relation to different host stages. A literature survey
reveals a trend for female parasitoids to feed preferentially or exclusively on earlier host stages and to oviposit preferentially
or exclusively in/or later ones.
We explore the relative advantages to host-feeding parasitoids of a number of possible host stage selection strategies. We
develop hypotheses, formalizing and testing them using modifications to our earlier simulation model of host-feeding strategies
(Jervis and Kidd, 1986).
We conclude from our modelling that the advantage to be gained from feeding on early host stages and ovipositing in late ones
is likely to be associated with: 1) reduced handling times when feeding on early stage hosts; 2) reduced wastage of progeny
from mortality factors other than host-feeding by the parent parasitoid, achieved by confining oviposition to late host stages;
and 3) reduced probability of progeny mortality resulting from the parent's host-feeding activities. 相似文献
797.
How does POSSLQ measure up? Historical estimates of cohabitation 总被引:1,自引:0,他引:1
We use March Current Population Survey (CPS) data from 1977 to 1997 to produce a new historical series of indirect cohabitation prevalence estimates. We compare our new estimates with those produced by the traditional method and evaluate the new estimates. We then compare the indirect estimates with the new direct estimates to investigate whether biases exist in the indirect estimates. Our findings indicate that the traditional indirect method of estimating cohabitation prevalence underestimates cohabitors in different subpopulations, especially among those with children. We also find that the new indirect measure produces relatively unbiased estimates of cohabitors' characteristics. 相似文献
798.
The duration of time between two successive births or between marriage and first birth is an indicator of the level of fertility of a couple. Potter and Parker (1964) and Singh (1961, 1967) have suggested the Type I Geometric as a distribution appropriate for representing the length of interval to first conception leading to a live birth. Potter and Parker estimated the parameters of this distribution with the help of the first two moments. Majumdar and Sheps (1970) pointed out the limitations of these moment estimates and gave a method to obtain maximum likelihood estimates, based on formulas which are too involved for solution without the help of a computer. Singh proposed a continuous probability distribution based on another set of assumptions for the above situation. He outlined a method to obtain best asymptotically normal estimates of the parameters. These estimates are obtained after several iterations starting from any set of consistent estimates. The objective of this paper is to show that it is relatively easier to obtain maximum likelihood estimates of the parameters of the continuous model, which describes the data on duration to first conception as well as does the discrete model. Simple expressions for the moment and maximum likelihood estimates with the corresponding covariance matrices are obtained. Application is made to three sets of data. 相似文献
799.
800.
Namboodiri NK 《Population studies》1972,26(3):465-485
Abstract In an earlier paper a working model of marital fertility was presented.(1) That model grew out of a close study of Becker's economic model for fertility analysis.(2) Becker's model was modified in several respects in order to meet a number of major objections levelled against it by Judith Blake, Deborah Freedman, and others.(3) The purpose of the present paper is to examine how far the model presented earlier can serve as a 'binder' for the interpretative schemes now available in the literature on fertility differentials. More specifically, the objective is to identify the underlying explanatory factors of a number of analytical hypotheses concerning fertility differentials, and to examine whether the factors thus identified can be located in the fertility model presented in the earlier paper.(4) Little attention will be paid to the causal directions, if any, recognized in the hypotheses studied, nor will we attempt to provide a systematic review of empirical findings. 相似文献