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961.
Barbara Fallon Nico Trocmé Melissa Van Wert Krista Budau Mary Ballantyne Kristen Lwin 《Journal of Social Work Education》2015,51(3):S271-S282
The objective of this article is to describe the successes and challenges of a unique knowledge mobilization initiative that was funded through the Social Sciences and Humanities Research Council of Canada. This initiative focused on promoting knowledge mobilization by increasing the capacity of child welfare organizations in Ontario to conduct and use research. Building on existing knowledge mobilization models in Ontario, this initiative brought university-based researchers together with child welfare practitioners to use existing data sets from the Ontario Incidence Studies of Reported Child Abuse and Neglect. Overall, this knowledge mobilization initiative resulted in several positive outcomes. Along with the successes, the research team faced several challenges in implementing this initiative, which are described in detail. 相似文献
962.
Jan De Loecker Pinelopi K. Goldberg Amit K. Khandelwal Nina Pavcnik 《Econometrica : journal of the Econometric Society》2016,84(2):445-510
This paper examines how prices, markups, and marginal costs respond to trade liberalization. We develop a framework to estimate markups from production data with multi‐product firms. This approach does not require assumptions on the market structure or demand curves faced by firms, nor assumptions on how firms allocate their inputs across products. We exploit quantity and price information to disentangle markups from quantity‐based productivity, and then compute marginal costs by dividing observed prices by the estimated markups. We use India's trade liberalization episode to examine how firms adjust these performance measures. Not surprisingly, we find that trade liberalization lowers factory‐gate prices and that output tariff declines have the expected pro‐competitive effects. However, the price declines are small relative to the declines in marginal costs, which fall predominantly because of the input tariff liberalization. The reason for this incomplete cost pass‐through to prices is that firms offset their reductions in marginal costs by raising markups. Our results demonstrate substantial heterogeneity and variability in markups across firms and time and suggest that producers benefited relative to consumers, at least immediately after the reforms. 相似文献
963.
Alexander Hogenboom Wolfgang Ketter Jan van Dalen Uzay Kaymak John Collins Alok Gupta 《决策科学》2015,46(4):791-818
In today's complex and dynamic supply chain markets, information systems are essential for effective supply chain management. Complex decision making processes on strategic, tactical, and operational levels require substantial timely support in order to contribute to organizations' agility. Consequently, there is a need for sophisticated dynamic product pricing mechanisms that can adapt quickly to changing market conditions and competitors' strategies. We propose a two‐layered machine learning approach to compute tactical pricing decisions in real time. The first layer estimates prevailing economic conditions—economic regimes—identifying and predicting current and future market conditions. In the second layer, we train a neural network for each regime to estimate price distributions in real time using available information. The neural networks compute offer acceptance probabilities from a tactical perspective to meet desired sales quotas. We validate our approach in the trading agent competition for supply chain management. When competing against the world's leading agents, the performance of our system significantly improves compared to using only economic regimes to predict prices. Profits increase significantly even though the prices and sales volume do not change significantly. Instead, tactical pricing results in a more efficient sales strategy by reducing both finished goods and components inventory costs. 相似文献
964.
965.
This study examines a deterministic material requirements planning (MRP) problem where lead times at subsequent ordering moments differ. Adequate replenishment methods that can cope with lead time differences are lacking because of the order crossover phenomenon, that is, replenishment orders are not received in the sequence they are ordered. This study specifies how to handle order crossovers and recalculate planned order releases after an update of gross requirements. The optimal (s, S) policy is based on dynamic programing. The state space is kept to a minimum due to three fundamental insights. The performance of the optimal solution approach is compared with two heuristics based on relaxations and a benchmark approach in which order crossovers are ignored. A numerical analysis reveals that average cost savings up to 25% are possible if the optimal policy is used instead of the benchmark approach. The contribution of this study is threefold: (1) it generalizes theory on MRP ordering, allowing for lead time differences and order crossovers; (2) it develops new fundamental insights and an optimal solution procedure, leading to substantial cost saving; and (3) it provides good‐performing heuristics for a general and realistic replenishment problem that can replace the current replenishment methods within MRP. 相似文献
966.
Hendrik Brumme Daniel Simonovich Wickham Skinner Luk N. Van Wassenhove 《Production and Operations Management》2015,24(10):1513-1523
Few unfocused factories outperform competitors, but focus is elusive because the environment is constantly evolving and this requires changes to a factory's key tasks. So how can focus be achieved and sustained? We present insights derived from an historical analysis of the German Hewlett‐Packard server plant which went through a series of focus changes over the years. Using this example, we provide clues for the right timing of focus changes and discuss critical structural and infrastructural changes required during the focus transitions, as well as cross‐functional coordination and leadership challenges. Our assertion is that production operations constitute a system that can adapt to disruptive change by using the levers of manufacturing policies to stay focused on a limited but absolutely essential task which creates a strategic advantage. 相似文献
967.
968.
Alan Roulstone Jan Walmsley Allan Sutherland Daniel Blackie 《Disability & Society》2007,22(3):329-337
969.
Serge Tardif Franois Bellavance Constance Van Eeden 《Revue canadienne de statistique》2005,33(4):471-488
The authors propose nonparametric tests for the hypothesis of no direct treatment effects, as well as for the hypothesis of no carryover effects, for balanced crossover designs in which the number of treatments equals the number of periods p, where p ≥ 3. They suppose that the design consists of n replications of balanced crossover designs, each formed by m Latin squares of order p. Their tests are permutation tests which are based on the n vectors of least squares estimators of the parameters of interest obtained from the n replications of the experiment. They obtain both the exact and limiting distribution of the test statistics, and they show that the tests have, asymptotically, the same power as the F‐ratio test. 相似文献
970.
Kristel Van Steen Benjamin A. Raby Geert Molenberghs Herbert Thijs Mieke De Wit Monika Peeters 《Pharmaceutical statistics》2005,4(3):203-214
The practice of sequence alignment is constantly oscillating between the risk of overlooking important structure and that of discovering any arbitrarily defined kind of structure anywhere. On the other hand, the use of a condensed consensus sequence may lead to a substantial loss in valuable information. While adopting a Mahalanobis‐type index we allow for a certain degree of uncertainty in the measurements. This uncertainty may be caused by inaccurate measurements or ambiguity. In this paper, we test the similarity between DNA sequences within the framework of equivalence testing, accounting for both variances and covariances between frequencies of nucleotides. Statistical methods for testing equivalence were first developed in the context of pharmacokinetics and later extended to the field of clinical trials. Nowadays, (bio)equivalence tests seem to be less frequently used outside the drug testing field, including statistical genetics. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献