The effects of workforce strategies on manufacturing operations

This paper tests the effects of three workforce strategies on a multistage, multiproduct manufacturing system under various operating conditions. These three strategies are those that are predominant in today's world economics. One type is a chase strategy, often used by firms that employ low skilled workers and faced with seasonal product demands, where workforce levels fluctuate according to increases and decreases in production requirements. A level-flexible strategy, commonly called the Toyota system, keeps the aggregate workforce at a constant size but by having flexibly trained workers it can allow transfers of workers between various departments and processes as production requirements dictate. The third major type is a level-inflexible strategy, such as that used on mass-assembly lines employed by American automobile manufacturers. Under this strategy, the number of workers remains constant in each department as well as at the aggregate level regardless of short term changes in the production requirements. The manufacturing system is envisioned as a sequential planning process with interrelated decisions made at the levels of aggregate planning, master production scheduling, and departmental planning. This process is modeled as a zero-one mixed integer program. The operating conditions under which the strategies are tested are the variability of demand, the level of service, and the degree of inventory investment. The strategies are statistically tested as to their effects on five criteria: average weekly workforce size, average quarterly inventory investment, average weekly overtime, total setups and the average weekly ratio of departmental load to capacity.Using four different products and an experimental manufacturing environment described within the paper, we tested for any statistical differences between the three strategies. We found that none of the strategies had significantly different workforce sizes. Also, the chase strategy had the smallest average quarterly inventory investment. This implies that the “Japanese” level-inflexible strategy does not have the smallest workforce or lowest inventory as claimed by some.We also tested the effects of the operating conditions on the workforce strategies. The level-flexible strategy was most insulated from the seasonality, inventory restrictions, and service level. Thus again the claims made for the level-inflexible strategy about being insulated from its environment were not substantiated. It was found that the seasonality of demand had the greatest impact on the three workforce strategies. Also, the level of service greatly affected the utilization of labor resources.The major overall conclusion is that the level-flexible strategy which is associated with some Japanese manufacturing firms does not achieve the claims that some of its adherents have made for it. It does not have the smallest workforce or the lowest inventory nor is it best insulated from its environment. Furthermore, the seasonality of demand and the level of service do effect this strategy.     

Predictability of future index returns based on the 52-week high strategy

In a landmark paper, George and Hwang (2004) show that a stock's 52-week high price largely explains the momentum effect and that a strategy based on closeness to the 52-week high has better forecasting power for future returns than do momentum strategies. We find that the 52-week high strategy is unprofitable when applied to emerging markets indices, and that it is significantly less profitable than the corresponding momentum strategy. Overall the 52-week high effect is not as pervasive as the momentum effect.     

Overnight stock returns,intraday returns,and firm-specific investor sentiment

In this study, we propose a new index for measuring firm-specific investor sentiment using overnight and intraday stock returns. We use actual equity data to construct the firm-level investor sentiment index and find that the new index has characteristics expected of a sentiment measure. In addition, we propose a novel sentiment-weighted trading strategy and apply it to momentum and short-term reversal strategies. We find that the sentiment-weighted trading strategy generates better performance in momentum and short-term reversal strategies. The sentiment-weighted trading strategy’s superior performance is evidence that our firm-level investor sentiment index possesses predictive powers with regard to future returns.     

Value investing anomalies in the European stock market: Multiple Value, Consistent Earner, and Recognized Value

Empirical academic studies have consistently found that value stocks outperform glamour stocks and the market as a whole. This article extends prevailing research on existing value anomalies. It evaluates simple value strategies for the European stock market (compared to many other studies that test market data on a country-by-country basis) as well as sophisticated multi-dimensional value strategies that also include capital return variables (Consistent Earner Strategy) and momentum factors (Recognized Value Strategy), the latter reconciling intermediate horizon momentum and long-term reversals of behavioral finance theories. It can be shown that these “enhanced” value strategies can produce superior returns compared to returns of the whole market or “simple” value strategies without capturing higher risks applying traditional risk measures.     

Positional momentum and liquidity management; a bivariate rank approach

This paper introduces a new positional momentum management strategy based on the expected future ranks of asset returns and trade volume changes predicted by a bivariate Vector Autoregressive (VAR) model. The new method is applied to a dataset of 1330 stocks traded on the NASDAQ between 2008 and 2016. It is shown that return ranks are correlated with their own past values and the current and past ranks of trade volume changes. This results leads to a new expected positional momentum strategy providing portfolios of predicted winners, conditional on past ranks of returns and volume changes. This approach further extends to positional liquidity management. The expected liquid positional strategy selects portfolios of stocks with the strongest realized or predicted increase in trading volume. These new positional management strategies outperform the standard momentum strategies and the equally weighted portfolio in terms of average returns and Sharpe ratio.     

S&P Global Sector survivals: Momentum effects in sector indices underlying iShares

This study investigates survival of the momentum effects in S&P Global 1200 Sector index returns which are underlying indices for iShares, by employing a methodology which allows analyzing the momentum effect without being dependant on zero-investment portfolios. We design a trading strategy based on momentum survival time for 10 S&P Global 1200 Sectors and show that for most of the sectors, long, short and long/short momentum strategies are profitable at the realistic level of transaction costs, generating substantially higher Sharpe ratios than buy and hold sector index strategy.     

Risk premia and seasonality in commodity futures

We develop and estimate a multifactor affine model of commodity futures that allows for stochastic seasonality. We document the existence of stochastic seasonal fluctuations in commodity futures and that properly accounting for the cost‐of‐carry curve requires at least three factors. We estimate the model using data on heating oil futures and analyze the contribution of the factors to risk premia. Correctly specifying seasonality as stochastic is important to avoid erroneously assigning those fluctuations to other risk factors. We also estimate a nonlinear version of the model that imposes the zero lower bound on interest rates and find similar results.     

An exploration of factors influencing the choice of commodity price risk mitigation strategies

Most firms are exposed to price volatility associated with commodities, which can significantly affect the price paid for raw materials, energy, packaging, shipping, and component purchases. Commodity price risk represents the financial, operational and informational effects of commodity price volatility (CPV). The purpose of this paper is to contribute to the supply chain risk management literature by providing a taxonomy of commodity price risk mitigation strategies and factors that may influence the adoption of these strategies. A qualitative study was conducted using a grounded theory approach, based on case studies of companies with home operations in Italy, Germany, and the US. The paper provides some initial evidence for theory and practice as to: 1) how firms can mitigate the risk from CPV by implementing various sourcing, contracting, and financing strategies; and 2) the influence of commodity/product factors, buying organization factors, supply chain factors, and external environment factors on strategy capability and choice.     

Momentum strategies with stock index exchange-traded funds

Previously reported momentum profits may not be available to individual investors who have more trading constraints. Therefore, I examine the profitability of momentum strategies with international iShares and US sector exchange-traded funds (ETFs) traded on the NYSE. The index ETFs provide individual investors easy access to international stock markets and US sectors for asset allocations. Using cross-sectional momentum strategies, in contrast to prior research, I find that momentum profits are insignificant for the late 1990s–2014 period. Few country and industry ETFs yield positive results using time series momentum, and the overall performance is worse than the buy-and-hold strategy. Time series momentum offers significant profits during the 2008 global financial crisis, but the profits decline sharply for the post-crisis period.     

The impact of a firm's make, pseudo-make, or buy strategy on product performance

The bulk of the product architecture and make-buy choice literature deals with product architecture changes from integral to modular form. This development is often associated with a firm's tendency to change from a make to a buy strategy. However, a few studies investigate the change of product architecture in the reverse direction - from modular to integral form - and the subsequent change in the firm sourcing decision from a buy to a make strategy. These studies hold to the presumption that a firm following a make strategy will outperform firms following a buy strategy in dealing with integral product architectures. Based on the knowledge-based view, we argue for the viability of a sourcing strategy between the pure make and buy strategies - a pseudo-make strategy. We also argue that as product architecture changes from a modular to integral form, firms adopting this pseudo-make strategy are likely to show better product performance than firms following a pure make or buy strategy due to the relative knowledge advantages of the pseudo-make strategy in dealing with the integral product architecture. We examine the impact of the make/pseudo-make/buy strategies on product performance in the U.S. bicycle derailleur and freewheel market from 1980 to 1992 and provide theoretical and managerial implications of our results. Our findings highlight an important distinction between the pseudo-make and make-buy strategies that has not previously been fully appreciated in the extant literature, and as a result increases our understanding of why some firms do not switch strategies from a buy to a make strategy when product architecture changes from modular to integral form as previously expected.     

Price gap anomaly in the US stock market: The whole story

This paper analyses the price gap anomaly in the US stock market (comprised of the DJI, S&P 500 and NASDAQ) covering the period 1928 to 2018. This paper aims to investigate whether or not price gaps create market inefficiencies. Price gaps occur when the current day’s opening price is different from the previous day’s closing price due orders placed before the opening of the market. Several hypotheses are tested using various statistical tests (Student’s t-test, ANOVA, Mann-Whitney test), regression analysis, and special methods, that is, the modified cumulative returns and the trading simulation approaches. We find strong evidence in favour of abnormal price movements after price gaps. We observe that during a gap day prices tend to change in the direction of the gap. A trading strategy based on this anomaly was efficient in that its results were not random, indicating that this market was not efficient. The momentum effect was found to be temporary and no evidence of seasonality in price gaps was found. Lastly, our results were also contrary to the myth that price gaps tend to get filled.     

Planned or Emergent Strategy Making? Exploring the Formation of Corporate Sustainability Strategies

In strategy research, there is a consensus that strategy making resides on a continuum from planned to emergent where most strategies are made in a mixed way. Different contingency factors have been suggested to explain the factors that influence strategy making. Sustainability research seems to overlook most of this development and assumes instead that sustainability strategies are made in a purely planned way. We contribute to a better understanding of the role of different strategy making modes for sustainability in three ways. First, we point to the bias towards planned strategy formation in sustainability research. Second, we propose a new contingency factor to help explain sustainability strategy making based on the nature of the problem addressed. Third, we discuss strategy making for different types of sustainability problems. We argue that planned strategy making is expected for salient and non‐wicked problems while emergent strategy making is likely for non‐salient and wicked problems. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment     

Simple collective equilibria in stopping games

At each moment in time, an alternative from a finite set is selected by a stochastic process. Players observe the selected alternative and sequentially cast a yes or a no vote. If the set of players casting a yes vote is decisive for the selected alternative, it is accepted and the game ends. Otherwise the next period begins. We refer to this class of problems as stopping games. Collective choice games, quitting games, and coalition formation games are particular examples. When the core of a stopping game is non-empty, a subgame perfect equilibrium in pure stationary strategies is shown to exist. But in general, even subgame perfect equilibria in mixed stationary strategies may not exist. We show that aggregate voting behavior can be summarized by a collective strategy. We insist on pure strategies, allow for simple forms of punishment, and provide a constructive proof to show that so-called two-step simple collective equilibria always exist. This implies the existence of a pure strategy subgame perfect equilibrium. We apply our approach to the case with three alternatives exhibiting a Condorcet cycle and to a model of redistributive politics.     

Large but finite games with asymmetric information

Carmona considered an increasing sequence of finite games in each of which players are characterized by payoff functions that are restricted to vary within a uniformly equicontinuous set and choose their strategies from a common compact metric strategy set. Then Carmona proved that each finite game in an upper tail of such a sequence admits an approximate Nash equilibrium in pure strategies.     

Invader strategies in the war of attrition with private information

Second price all-pay auctions (wars of attritions) have an evolutionarily stable equilibrium in pure strategies if valuations are private information. I show that for any level of uncertainty there exists a pure deviation strategy arbitrarily close to the equilibrium strategy such that for some valuations the equilibrium strategy has a selective disadvantage against the deviation if the population mainly plays the deviation strategy. I show that agents with those valuations would prefer to deviate even farther from the equilibrium strategy, if the population collectively uses the deviation strategy. I argue that in the Bayesian game studied here, a mass deviation can be caused by the entry of a small group of agents. The results provided in this paper imply that the equilibrium strategy is indeed unstable if one considers rare and independent mutations on the space of valuations. Numeric calculations indicate that the closer the deviation strategy to the equilibrium strategy, the more valuations are destabilizing.     

基于企业生命周期的财务战略选择

在企业生命周期的不同发展阶段,由于企业所处环境不同,面临的风险内涵和强度特征也不尽相同,从而直接影响到企业财务战略的选择。本文首先概述财务战略的内涵,并将其目标定位于企业可持续发展,在此基础上分析企业生命周期不同阶段的风险特征,进而提出各阶段适宜的财务战略选择。     

风险转移的常见策略分析

风险转移策略是企业风险处理的常见策略之一。本文对风险转移策略进行了分类,并分别从保险、外包与出售等角度探讨了企业实现风险转移策略的机理与特点。     

Gender equality still on the European agenda—but for how long?

While the momentum has certainly not yet disappeared from the gender equality agenda within Europe, the impact of that agenda remains patchy. Progress within individual member states has been significant but not always steady or cumulative. At the European level more attention has been paid to the gender pay gap but policy initiatives remain weak. The loss of the equal opportunities pillar in the new employment guidelines puts this momentum at risk but the new phase still includes commitments to an integrated strategy of gender mainstreaming and equal opportunities.     

First-price auctions where one of the bidders’ valuations is common knowledge

We analyze a private and independent valuation first-price auction under the assumption that one of the bidders’ valuations is common knowledge. We show that no pure strategy equilibrium exists and we characterize a mixed strategy equilibrium in which the bidder whose valuation is common knowledge randomizes her bid while the other bidders play pure strategies. In an example with the uniform distribution, we compare the expected profits of seller and buyers in this auction with those in a standard symmetric private valuation model.