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941.
Many telephone call centers that experience cyclic and random customer demand adjust their staffing over the day in an attempt to provide a consistent target level of customer service. The standard and widely used staffing method, which we call the stationary independent period by period (SIPP) approach, divides the workday into planning periods and uses a series of stationary independent Erlang‐c queuing models—one for each planning period—to estimate minimum staffing needs. Our research evaluates and improves upon this commonly used heuristic for those telephone call centers with limited hours of operation during the workday. We show that the SIPP approach often suggests staffing that is substantially too low to achieve the targeted customer service levels (probability of customer delay) during critical periods. The major reasons for SIPP‘ s shortfall are as follows: (1) SIPP's failure to account for the time lag between the peak in customer demand and when system congestion actually peaks; and (2) SIPP’ s use of the planning period average arrival rate, thereby assuming that the arrival rate is constant during the period. We identify specific domains for which SIPP tends to suggest inadequate staffing. Based on an analysis of the factors that influence the magnitude of the lag in infinite server systems that start empty and idle, we propose and test two simple “lagged” SIPP modifications that, in most situations, consistently achieve the service target with only modest increases in staffing.  相似文献   
942.
They do a great job. So we promote them. Now they supervise people who don't do the job as well as they did. We give them a big raise. But because they're exempt they make less than their leads. They have the toughest job in the company—managing people. So we grant them an entire day of training to prepare. We ask them to mentor, coach, and have close relationships with their direct reports—all 132 of them. Then when the stock dips, we blame “middle management” and lay a bunch of them off.  相似文献   
943.
This article proposes a programme approach for achieving the social and economic reintegration of all categories of return migrants. As former exiles who have returned to their country of origin are no longer refugees, some government agencies need to organize the reception of, and provide assistance to, returnees. But without long-term planning, ad hoc committees are unable to be effective facilitators of the reintegration process. The article suggests a list of major elements necessary for an effective reintegration programme, and argues that governments should focus on the institutional mechanism of programme management, including the creation of a responsible agency or agencies. The management structure should be based in the National Planning Ministry of government. Establishment of an effective mechanism would be likely to inspire donor confidence; and 'homecoming' would no longer be a nightmare for potential returnees trying to reintegrate.  相似文献   
944.
In May 2004, the Australian government announced a “Baby Bonus” policy, paying women an initial A$3,000 per new child. We use household panel data from the Household, Income and Labour Dynamics in Australia Survey (N = 14,932) and a simultaneous equations approach to analyze the effects of this bonus on fertility intentions and ultimately births. The results indicate that opportunity costs influence intentions and births in predictable ways. Fertility intentions rose after the announcement of the Baby Bonus, and the birth rate is estimated to have risen modestly as a result. The marginal cost to the government for an additional birth is estimated to be at least A$3,000 per new child. We use household panel data from the Household, Income and Labour Dynamics in Australia Survey (N = 14,932) and a simultaneous equations approach to analyze the effects of this bonus on fertility intentions and ultimately births. The results indicate that opportunity costs influence intentions and births in predictable ways. Fertility intentions rose after the announcement of the Baby Bonus, and the birth rate is estimated to have risen modestly as a result. The marginal cost to the government for an additional birth is estimated to be at least A126,000.  相似文献   
945.
Axinn WG  Link CF  Groves RM 《Demography》2011,48(3):1127-1149
To address declining response rates and rising data-collection costs, survey methodologists have devised new techniques for using process data (“paradata”) to address nonresponse by altering the survey design dynamically during data collection. We investigate the substantive consequences of responsive survey design—tools that use paradata to improve the representative qualities of surveys and control costs. By improving representation of reluctant respondents, responsive design can change our understanding of the topic being studied. Using the National Survey of Family Growth Cycle 6, we illustrate how responsive survey design can shape both demographic estimates and models of demographic behaviors based on survey data. By juxtaposing measures from regular and responsive data collection phases, we document how special efforts to interview reluctant respondents may affect demographic estimates. Results demonstrate the potential of responsive survey design to change the quality of demographic research based on survey data.  相似文献   
946.
This research examines the use of both frozen and replanning intervals for planning the master production schedule (MPS) for a capacity-constrained job shop. The results show that forecast error, demand lumpiness, setup time, planned lead time, and order size have a greater impact on the mean total backlog, total inventory, and number of setups than the frozen and replanning intervals. The study also shows that a repetitive lot dispatching rule reduces the importance of lot sizing, and a combination of repetitive lot dispatching rule and single-period order size consistently produces the lowest mean total backlog and total inventory. The results also indicate that rescheduling the open orders every period produces a lower mean total backlog and total inventory when the forecast errors are large relative to the order sizes. This result suggests that the due date of an open order should be updated only when a significant portion of the order is actually needed on the new due date.  相似文献   
947.
948.
In the past 15 years, research activities focusing on the interlinkages between climate change and human mobility have intensified. At the same time, an increasing number of actors and processes have sought to address human mobility in the context of climate change from a policy perspective. Hitherto, research has been limited in terms of geographical preferences as well as conceptual and methodological focus areas. This paper argues that to address the evolving policy space, future research on climate change in the context of human mobility needs to become more differentiated, integrated and generalized. This includes concerted efforts to better integrate researchers from the global South, improved cross-linkages between different datasets, approaches and disciplines, more longitudinal and comparative studies and development of innovative qualitative and quantitative methods.  相似文献   
949.
950.
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