Estimators of vital events in dual-record systems

Dual-record system estimation has been widely used to obtain vital events in the past. Because of the weakness of the statistical assumptions of the model, as well as the biases involved in the estimators, its use became limited. The proposed estimators for dual-record systems are based on further division of the cells of the original table. The results have shown that they improved the underestimation of the total counts when compared with the classical Chandra Sekar-Deming estimator.     

Design Principles for Flexible Systems

A fundamental aspect of designing systems with dedicated servers is identifying and improving the system bottlenecks. We extend the concept of a bottleneck to networks with heterogeneous, flexible servers. In contrast with a network with dedicated servers, the bottlenecks are not a priori obvious, but can be determined by solving a number of linear programming problems. Unlike the dedicated server case, we find that a bottleneck may span several nodes in the network. We then identify some characteristics of desirable flexibility structures. In particular, the chosen flexibility structure should not only achieve the maximal possible capacity (corresponding to full server flexibility), but should also have the feature that the entire network is the (unique) system bottleneck. The reason is that it is then possible to shift capacity between arbitrary nodes in the network, allowing the network to cope with demand fluctuations. Finally, we specify when certain flexibility structures (in particular chaining, targeted flexibility, and the “N” and “W” structures from the call center literature) possess these desirable characteristics.     

Married women’s added worker effect during the 2008 economic crisis—The case of Turkey

This paper analyzes the labor supply response of married women as a result of their husbands’ job losses (‘added worker effect’). The study uses panel data from Turkey to test the presence of an added worker effect during the global economic crisis of 2008. Identification is achieved by an instrumental variable approach. In particular, an exogenous variation in the output of male-dominated sectors induced by the crisis is used as an instrument for the husbands’ unemployment. Results show that the probability of a woman participating in the labor force increases by 15–28% in response to her husband’s unemployment. However, the effect is not contemporaneous; rather, it appears with a lag of one quarter and only operates for two quarters. The effect is mainly driven by financially-constrained (less-educated and young) couples, which suggests the prevalence of an income effect in spousal labor supply decisions.     

Flexible Servers in Understaffed Tandem Lines

We study the dynamic assignment of cross‐trained servers to stations in understaffed lines with finite buffers. Our objective is to maximize the production rate. We identify optimal server assignment policies for systems with three stations, two servers, different flexibility structures, and either deterministic service times and arbitrary buffers or exponential service times and small buffers. We use these policies to develop server assignment heuristics for Markovian systems with larger buffer sizes that appear to yield near‐optimal throughput. In the deterministic setting, we prove that the best possible production rate with full server flexibility and infinite buffers can be attained with partial flexibility and zero buffers, and we identify the critical skills required to achieve this goal. We then present numerical results showing that these critical skills, employed with an effective server assignment policy, also yield near‐optimal throughput in the Markovian setting, even for small buffer sizes. Thus, our results suggest that partial flexibility is sufficient for near‐optimal performance, and that flexibility structures that are effective for deterministic and infinite‐buffered systems are also likely to perform well for finite‐buffered stochastic systems.