Language as Both Human Capital and Ethnicity1

In this study, we estimate earnings differentials for knowledge of thirteen minority languages in Canada's three largest urban area. We find that conditional on knowledge of a majority language, knowledge of a minority language is associated with lower earnings. However, the negative differential diminishes for those languages with large local populations. This suggests a positive human capital effect which is for the most part swamped by a negative factor. We argue that this factor is a reflection of ethnicity operating either through ethnolinguistic labor market enclaves or labor market discrimination against minorities.     

A Numerical Solution to the Nonhomogeneous Two-Stage MVK Model of Cancer

In this article, we describe a straightforward method for solving the probability of at least one malignant cell by time t, and the associated hazard function, in the general (i.e., nonhomogeneous) two-stage Moolgavkar-Venzon-Knudson (MVK) model of cancer. The method consists of solving four coupled ordinary differential equations derived from the Kolmogorov backward equations for this process. The relationship of this method to previously proposed solutions is discussed.     

Which Child Immigrants Face Earnings Disparity? Age‐at‐immigration,Ethnic Minority Status and Labour Market Attainment in Canada

Using Canadian Census microdata from 1990 to 2005, we investigate the earnings attainment of immigrants to Canada in 6 age‐at‐arrival cohorts. In comparison to past work we extend our understanding regarding three dimensions of the age at immigration debate: we explore heterogeneity across fine grained age‐at‐arrival cohorts, over a fifteen‐year period and across different ethnic groups. We find that white immigrants and female immigrants arriving in Canada prior to age 18 face little earnings disparity. In contrast, visible minority male immigrants face significant earnings disparity regardless of their age‐at‐migration, and additionally this disparity increases sharply with age‐at‐migration. We find a break in earnings attainment at an age‐of‐arrival of 17, with immigrants arriving after this age performing much worse than those arriving at this age or earlier. The patterns observed are found for visible minority immigrants as a whole, and for Chinese, South Asian and African/Black origin immigrants examined separately.     

Exploring the role of faith in resettlement among Muslim Syrian refugees

ABSTRACT

Over 95% of the refugees from Syria who have resettled in the United States are Muslim. The purpose of this qualitative study was to explore the role of the Islamic faith in contributing to resiliency among recently resettled refugees from Syria. Ten in-depth, semi-structured interviews were conducted with Syrian adults who had arrived in the United States between 3 months and 2 years prior to the study. Findings emphasized the primary role of the Islamic faith in the lives of participants. For participants in this study, identifying as Muslim was an essential part of their identity and served as a source of comfort, strength, pride, and humility. Parents in the study expressed fears that their children would lose their connection to their culture and would grow up to devalue the Islamic faith and traditional religious practices due to their exposure to American values which they viewed less strict regarding dress, alcohol consumption, and faith practices. Understanding the important role that the Islamic faith can have in providing a source of comfort, strength, and empowerment for Syrian refugees, and working to build infrastructure to support and sustain these faith traditions is an essential component of refugee resettlement in the United States.     

An Evaluation of Capacity Sensitive Order Review and Release Procedures in Job Shops

We investigate the performance of capacity-sensitive order review and release (ORR) procedures in job shop environments that have not been previously explored. Previous research has ignored the case of job shops which must perform to very tight due-dates because of time-sensitive customers. We propose and test a new capacity sensitive ORR procedure called path based bottleneck (PBB) in such environments, along with the modified infinite loading (MIL) procedure which has been shown to work well in several studies. We compare the performance of these two controlled release rules with that of immediate release rule under different conditions of capacity utilization and customer specified exogenous duedates. Our results indicate that PBB performs well in lowering total costs when due-dates are tight, while MIL is a better procedure with relatively loose to medium due-dates. We also show that in many cases, the shortest processing time (SPT) dispatching rule is a superior performer than a due-date based rule like critical ratio (CR); a conclusion which is contrary to the existing research in this area. In addition, the shop floor control policies recommended are shown to be sensitive to the cost structure of the firm. The managerial implications of this research in providing effective shop floor control in job shops operating under tight due-date conditions are also discussed.     

The Impact of Learning and Labor Attrition on Worker Flexibility in Dual Resource Constrained Job Shops

This study investigates the impact of worker learning, worker flexibility, and labor attrition on the system performance of a dual resource constrained (DRC) job-shop. The effects of learning and labor attrition have not been previously addressed in DRC literature. Results from the study, consistent with previous literature, show that the greatest benefits are achieved when inter-departmental worker flexibility is incrementally introduced into the system. In addition, the learning environment, which depends on the initial processing time of jobs and the learning rates of workers, is shown to impact the acquisition of flexibility. The study also shows that the impact of labor attrition on system performance under certain shop conditions may be significant.     

Resource Flexibility Issues in Multistage Manufacturing

We test the situational impact of two types of resource flexibility, machine flexibility and labor flexibility, in a material requirements planning (MRP)-driven production system. Machine flexibility has not been treated in prior multistage research, only labor flexibility. Machine flexibility is closely related to a plant's positioning strategy. A process-focused plant opts for considerable machine flexibility by choosing general-purpose equipment. Resource flexibility, if effective, can be an attractive alternative to two other types of buffers, inflated inventories and costly capacity cushions. Our simulation results, using factor settings established earlier by a panel of managers, show that resource flexibility is indeed an effective buffer against uncertainties such as end-item demand variability, capacity bottlenecks, equipment failures, and yield losses. Machine flexibility is especially helpful in environments characterized by high uncertainties, tight capacities, and large lot sizes. Worker flexibility has a similar, but less dramatic, impact. Benefits are most striking with customer service, rather than with inventory or labor productivity. Finally, we show that simultaneous introduction of both machine and labor flexibility yields only marginal improvements over either kind of flexibility alone.     

Multiple facility location on a network with linear reliability order of edges

We study the problem of locating facilities on the nodes of a network to maximize the expected demand serviced. The edges of the input graph are subject to random failure due to a disruptive event. We consider a special type of failure correlation. The edge dependency model assumes that the failure of a more reliable edge implies the failure of all less reliable ones. Under this dependency model called Linear Reliability Order (LRO) we give two polynomial time exact algorithms. When two distinct LRO’s exist, we prove the total unimodularity of a linear programming formulation. In addition, we show that minimizing the sum of facility opening costs and expected cost of unserviced demand under two orderings reduces to a matching problem. We prove NP-hardness of the three orderings case and show that the problem with an arbitrary number of orderings generalizes the deterministic maximum coverage problem. When a demand point can be covered only if a facility exists within a distance limit, we show that the problem is NP-hard even for a single ordering.     

On tail behaviour of kth upper order statistics under fixed and random sample sizes via tail equivalence

For a fixed positive integer k, limit laws of linearly normalized kth upper order statistics are well known. In this article, a comprehensive study of tail behaviours of limit laws of normalized kth upper order statistics under fixed and random sample sizes is carried out using tail equivalence which leads to some interesting tail behaviours of the limit laws. These lead to definitive answers about their max domains of attraction. Stochastic ordering properties of the limit laws are also studied. The results obtained are not dependent on linear norming and apply to power norming as well and generalize some results already available in the literature. And the proofs given here are elementary.