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51.
This paper is a conceptual and methodological critique of arguments advanced by Ones and Viswesvaran (1996, this issue) favoring ‘broad’ over ‘narrow’ personality traits for personnel selection and theoretical explanation. We agree with Ones and Viswesvaran that predictors should match criteria in terms of specificity. We depart from them, however, in our view of how traits should be chosen to obtain the best possible prediction and explanation of a complex overall job performance criterion. We argue that the best criterion-related validities will be attained if researchers use a construct-oriented approach to match specific traits (i.e. traits narrower than the Big Five) to those specific job performance dimensions that have been found to be job relevant. We further argue that researchers should focus on development of theories of job performance that incorporate constructs that are both specific and meaningful. If researchers seek to emphasize only overall job performance and personality traits greater than or equal to the Big Five in breadth, we will fail to acquire a great deal of important knowledge about the nature and causes of important aspects of work behavior. 相似文献
52.
Modern Insect Extinctions, the Neglected Majority 总被引:5,自引:0,他引:5
ROBERT R. DUNN† 《Conservation biology》2005,19(4):1030-1036
Abstract: Most extinctions estimated to have occurred in the historical past, or predicted to occur in the future, are of insects. Despite this, the study of insect extinctions has been neglected. Only 70 modern insect extinctions have been documented, although thousands are estimated to have occurred. By focusing on some of the 70 documented extinctions as case studies, I considered ways in which insect extinctions may differ from those of other taxa. These case studies suggested that two types of extinction might be common for insects but rare for other taxa: extinction of narrow habitat specialists and coextinctions of affiliates with the extinctions of their hosts. Importantly, both of these forms of extinction are often ignored by conservation programs focused on vertebrates and plants. Anecdotal evidence and recent simulations suggest that many insect extinctions may have already occurred because of loss of narrow habitat specialists from restricted habitats and the loss of hosts. If we are serious about insect conservation, we need to spend more time and money documenting such extinctions. To neglect such extinctions is to ignore the majority of species that are or were in need of conservation. 相似文献
53.
MICHAEL R. BOSWELL ROBERT E. DEYLE RICHARD A. SMITH E. JAY BAKER 《Environmental management》1999,23(3):359-372
/ A method is presented for estimating probable public costs resulting from damage caused by hurricanes, measured as local government expenditures approved for reimbursement under the Stafford Act Section 406 Public Assistance Program. The method employs a multivariate model developed through multiple regression analysis of an array of independent variables that measure meteorological, socioeconomic, and physical conditions related to the landfall of hurricanes within a local government jurisdiction. From the regression analysis we chose a log-log (base 10) model that explains 74% of the variance in the expenditure data using population and wind speed as predictors. We illustrate application of the method for a local jurisdiction-Lee County, Florida, USA. The results show that potential public costs range from $4.7 million for a category 1 hurricane with winds of 137 kilometers per hour (85 miles per hour) to $130 million for a category 5 hurricane with winds of 265 kilometers per hour (165 miles per hour). Based on these figures, we estimate expected annual public costs of $2.3 million. These cost estimates: (1) provide useful guidance for anticipating the magnitude of the federal, state, and local expenditures that would be required for the array of possible hurricanes that could affect that jurisdiction; (2) allow policy makers to assess the implications of alternative federal and state policies for providing public assistance to jurisdictions that experience hurricane damage; and (3) provide information needed to develop a contingency fund or other financial mechanism for assuring that the community has sufficient funds available to meet its obligations. KEY WORDS: Hurricane; Public costs; Local government; Disaster recovery; Disaster response; Florida; Stafford Act 相似文献
54.
ROBERT M. DORAZIO 《Environmental and Ecological Statistics》1997,4(3):235-246
A general framework is developed for modelling rates of survival and recovery of marked animal populations in terms of auxiliary information collected at the time of marking. The framework may be used to estimate differences in survival or recovery among individual animals, groups of animals, and recovery times. Analyses of the recoveries of tagged fish and banded bird populations are used to illustrate the specification and selection of various models. 相似文献
55.
J. KEVIN SUMMERS STEPHEN B. WEISBERG A. FREDERICK HOLLAND JINGYEE KOU VIRGINIA D. ENGLE DENISE L. BREITBERG ROBERT J. DIAZ 《Environmental monitoring and assessment》1997,45(3):321-330
Dissolved oxygen concentration, which is often measured inestuaries to quantify the results of and stresses associatedwith eutrophication, can be highly variable with time of dayand tidal stage. To assess how well dissolved oxygenconditions are characterized by typical monitoring programs,we conducted Monte Carlo sampling from 16 semi-continuous,31-day dissolved oxygen records collected from estuaries alongthe Atlantic and Gulf coasts to mimic three samplingstrategies: (1) systematic point-in-time sampling, (2) randompoint-in-time sampling, and (3) short-term continuous records.These strategies were evaluated for their accuracy inestimating mean oxygen concentration, minimum oxygenconcentration, and percent of time below a threshold value of2 ppm. Mean dissolved oxygen concentration was most accuratelyestimated in both estuarine regions by random point-in-timesampling, but this strategy required more than ten samplingsper month for the estimate to be within 0.5 ppm on 50% of thesimulations. Short-term continuous sampling (24–48 h)correctly identified estuaries in the Gulf of Mexico regionwhere dissolved oxygen concentrations of less than 2 ppm wereexperienced greater than 20% of the time. However, largetidal variations in Atlantic coast estuaries showed thismeasure to be inaccurate in these estuarine environments. Noneof the sampling strategies correctly identified month-longoxygen minima within 0.5 ppm for more than 50% of thesimulations. This inability to characterize correctlydissolved oxygen conditions could add significant uncertaintyto risk assessments, waste load allocation models, and otherwater quality evaluations that are the basis for developingwastewater treatment strategies and requirements. Perhaps moreimportantly, the inaccuracy with which conventional samplingprocedures characterize minimum dissolved oxygen valuessuggests that the extent of hypoxia in estuarine waters inbeing substantially underestimated. 相似文献
56.
Overabundance: An Issue for Conservation Biologists? 总被引:4,自引:1,他引:4
57.
RICHARD FRANKHAM JONATHAN D. BALLOU MARK D. B. ELDRIDGE ROBERT C. LACY KATHERINE RALLS MICHELE R. DUDASH CHARLES B. FENSTER 《Conservation biology》2011,25(3):465-475
Abstract: Fragmentation of animal and plant populations typically leads to genetic erosion and increased probability of extirpation. Although these effects can usually be reversed by re‐establishing gene flow between population fragments, managers sometimes fail to do so due to fears of outbreeding depression (OD). Rapid development of OD is due primarily to adaptive differentiation from selection or fixation of chromosomal variants. Fixed chromosomal variants can be detected empirically. We used an extended form of the breeders’ equation to predict the probability of OD due to adaptive differentiation between recently isolated population fragments as a function of intensity of selection, genetic diversity, effective population sizes, and generations of isolation. Empirical data indicated that populations in similar environments had not developed OD even after thousands of generations of isolation. To predict the probability of OD, we developed a decision tree that was based on the four variables from the breeders’ equation, taxonomic status, and gene flow within the last 500 years. The predicted probability of OD in crosses between two populations is elevated when the populations have at least one of the following characteristics: are distinct species, have fixed chromosomal differences, exchanged no genes in the last 500 years, or inhabit different environments. Conversely, the predicted probability of OD in crosses between two populations of the same species is low for populations with the same karyotype, isolated for <500 years, and that occupy similar environments. In the former case, we recommend crossing be avoided or tried on a limited, experimental basis. In the latter case, crossing can be carried out with low probability of OD. We used crosses with known results to test the decision tree and found that it correctly identified cases where OD occurred. Current concerns about OD in recently fragmented populations are almost certainly excessive. 相似文献
58.
Health Assessment of the 1985 Flood Disaster in Puerto Rico 总被引:2,自引:0,他引:2
VANCE J. DIETZ JOSE G. RIGAU-PEREZ LEE SANDERSON LYDIA DIAZ ROBERT A. GUNN 《Disasters》1990,14(2):164-170
In Puerto Rico, during October 1985, tropical storm Isabel caused widespread flooding, landslides, and collapsing of bridges. A maximum of 180 persons died, including an estimated 127 at a landslide where the majority (78%) of deaths resulted from traumatic injury. Approximately 3,000 homes were damaged with 4,400 persons temporarily displaced into 44 shelters. A shelter surveillance system was established to monitor 19 acute and chronic conditions in 28 shelters during a 5-week period. Trend analysis trends of selected reportable communicable diseases in the general community revealed no changes attributable to the disaster in the 12 most severely affected municipalities. In these municipalities, the number of persons using the scheduled outpatient clinics after the disaster decreased significantly, but the mean daily number of emergency room visits did not show significant change. Analysis of surveillance data showed that no infectious disease outbreaks had occurred in the shelters. The post-impact health consequences resulting from this widespread flooding were minimal. Even so, disease surveillance remains essential for efficacious resource allocation and prevention strategies. 相似文献
59.
When Agendas Collide: Human Welfare and Biological Conservation 总被引:3,自引:0,他引:3
KAI M. A. CHAN‡ ROBERT M. PRINGLE JAI RANGANATHAN CAROL L. BOGGS YVONNE L. CHAN PAUL R. EHRLICH PETER K. HAFF§ NICOLE E. HELLER KARIM AL-KHAFAJI DENA P. MACMYNOWSKI† 《Conservation biology》2007,21(1):59-68
Abstract: Conservation should benefit ecosystems, nonhuman organisms, and current and future human beings. Nevertheless, tension among these goals engenders potential ethical conflicts: conservationists' true motivations may differ from the justifications they offer for their activities, and conservation projects have the potential to disempower and oppress people. We reviewed the promise and deficiencies of integrating social, economic, and biological concerns into conservation, focusing on research in ecosystem services and efforts in community-based conservation. Despite much progress, neither paradigm provides a silver bullet for conservation's most pressing problems, and both require additional thought and modification to become maximally effective. We conclude that the following strategies are needed to make conservation more effective in our human-dominated world. (1) Conservation research needs to integrate with social scholarship in a more sophisticated manner. (2) Conservation must be informed by a detailed understanding of the spatial, temporal, and social distributions of costs and benefits of conservation efforts. Strategies should reflect this understanding, particularly by equitably distributing conservation's costs. (3) We must better acknowledge the social concerns that accompany biodiversity conservation; accordingly, sometimes we must argue for conservation for biodiversity's sake, not for its direct human benefits. 相似文献
60.
Estimating the Effect of Protected Lands on the Development and Conservation of Their Surroundings 总被引:1,自引:0,他引:1
ROBERT I. McDONALD †† CHRIS YUAN-FARRELL† CHARLES FIEVET‡ MATTHIAS MOELLER§ PETER KAREIVA† DAVID FOSTER TED GRAGSON‡ ANN KINZIG§ LAUREN KUBY CHARLES REDMAN 《Conservation biology》2007,21(6):1526-1536
Abstract: The fate of private lands is widely seen as key to the fate of biodiversity in much of the world. Organizations that work to protect biodiversity on private lands often hope that conservation actions on one piece of land will leverage the actions of surrounding landowners. Few researchers have, however, examined whether protected lands do in fact encourage land conservation nearby or how protected lands affect development in the surrounding landscape. Using spatiotemporal data sets on land cover and land protection for three sites (western North Carolina, central Massachusetts, and central Arizona), we examined whether the existence of a protected area correlates with an increased rate of nearby land conservation or a decreased rate of nearby land development. At all sites, newly protected conservation areas tended to cluster close to preexisting protected areas. This may imply that the geography of contemporary conservation actions is influenced by past decisions on land protection, often made for reasons far removed from concerns about biodiversity. On the other hand, we found no evidence that proximity to protected areas correlates with a reduced rate of nearby land development. Indeed, on two of our three sites the development rate was significantly greater in regions with more protected land. This suggests that each conservation action should be justified and valued largely for what is protected on the targeted land, without much hope of broader conservation leverage effects. 相似文献