The Failure of Practical Intuition: How Forward‐Coverage Inventory Targets Cause the Landslide Effect

Seasonal demand for products is common at many companies including Kraft Foods, Case New Holland, and Elmer's Products. This study documents how these, and many other companies, experience bloated inventories as they transition from a low season to a high season and a severe drop in service levels as they transition from a high season to a low season. Kraft has termed this latter phenomenon the “landslide effect.” In this study, we present real examples of the landslide effect and attribute its root cause to a common industry practice employing forward days of coverage when setting inventory targets. While inventory textbooks and academic articles prescribe correct ways to set inventory targets, forward coverage is the dominant method employed in practice. We investigate the magnitude and drivers of the landslide effect through both an analytical model and a case study. We find that the effect increases with seasonality, lead time, and demand uncertainty and can lower service by an average of ten points at a representative company. While the logic is initially counterintuitive to many practitioners, companies can avoid the landslide effect by using demand forecasts over the preceding lead time to calculate safety stock targets.     

Incentive Contracts for Managing a Project with Uncertain Completion Time

We examine two time‐related incentive project management contracts (C1 and C2 contracts) when the manager conducts a reverse auction. Under the C1 contract, the contractor with the lowest bid price wins; however, the manager imposes a linear and symmetric incentive/disincentive for early/late completion according to a pre‐specified due date. Under the C2 contract, the winning contractor has the lowest composite score that is based on the quoted price and the quoted due date; however, in addition to the linear and symmetric penalty/incentive, the contractor is subject to an additional penalty for late completion. While the C2 contract is more sophisticated than the C1 contract (in terms of the number of decisions that each party has to make), our analysis reveals that, unless the project is truly urgent, the more complicated C2 contract adds no value to the manager— the simple C1 contract will suffice.     

Interethnic Romantic Relationships: Enacting Affiliative Ethnic Identities

Through in‐depth interviews with respondents who were in interethnic relationships (N = 28), the authors extended and refined a new approach to mate selection based on affiliative ethnic identities (T. Jimenez, 2010). Rather than assimilation and a breakdown of ethnic group boundaries, they found that people pursued interethnic relationships because of the ethnic differences they include. These relationships gave them access to an affiliate ethnic or multicultural identity. This perspective does not challenge but rather complements existing theories of mate selection, including the role of opportunity structures, exchange of benefits, and growing acceptance of or freedom to pursue interethnic relationships. Ethnic differences can remain central as people meet, fall in love, and marry across these differences.     

Varieties of Entrepreneurial Capitalism: The Culture of Entrepreneurship and Structural Inequalities of Work and Business Creation

As the labor market has changed over recent decades, a distinctive culture has evolved in tandem, epitomized by the innovation and dynamism of Silicon Valley. This culture of entrepreneurship celebrates autonomy and risk‐taking, legitimizes a shift toward flexible, contingent, and precarious work, and compels workers to continuously network, self‐improve, and self‐promote. This culture has helped to disseminate entrepreneurial practices to sectors of the economy traditionally characterized by stability and job security. We shed light on these changes by putting forward a new typology distinguishing between four ideal types of entrepreneurial activity: Silicon Valley entrepreneurship, Main Street entrepreneurship, corporate entrepreneurship, and entrepreneurial self‐employment. Each adopts the language and normative behaviors of the culture of entrepreneurship, but the ‘entrepreneurs’ working within these domains enjoy starkly different levels of creative and financial autonomy. Integrating scholarship on economic sociology, work and labor, cultural sociology, and critical theory, we explore the underlying dynamics of entrepreneurship that cut across institutional contexts in unexpected and sometimes contradictory ways. The conceptual understanding of entrepreneurship we put forward recognizes both entrepreneurship's relationship to past forms of business creation and its contemporary cultural influence, while also underscoring the various constraints and inequalities intrinsic to these forms of market activity.     

A PARTIAL INDEPENDENCE ITEM RESPONSE MODEL FOR SURVEYS WITH FILTER QUESTIONS

In many surveys, responses to earlier questions determine whether later questions are asked. The probability of an affirmative response to a given item is therefore nonzero only if the participant responded affirmatively to some set of logically prior items, known as "filter items." In such surveys, the usual conditional independence assumption of standard item response models fails. A weaker "partial independence" assumption may hold, however, if an individual's responses to different items are independent conditional on the item parameters, the individual's latent trait, and the participant's affirmative responses to each of a set of filter items. In this paper, we propose an item response model for such "partially independent" item response data. We model such item response patterns as a function of a person-specific latent trait and a set of item parameters. Our model can be seen as a generalized hybrid of a discrete-time hazard model and a Rasch model. The proposed procedure yields estimates of (1) person-specific, interval-scale measures of a latent trait (or traits), along with person-specific standard errors of measurement; (2) conditional and marginal item severities for each item in a protocol; (3) person-specific conditional and marginal probabilities of an affirmative response to each item in a protocol; and (4) item information and total survey information. In addition, we show here how to investigate and test alternative conceptions of the dimensionality of the latent trait(s) being measured. Finally, we compare our procedure with a simpler alternative approach to summarizing data of this type.     

Web Survey Design: Paging versus Scrolling

A key choice in the design of Web surveys is whether to placethe survey questions in a multitude of short pages or in longscrollable pages. There are advantages and disadvantages ofeach approach, but little empirical evidence to guide the choice.In 2003 we conducted a survey of over 21,000 undergraduate students.Ten percent of the 10,000 respondents were directed to the scrollableversion of the survey, containing a single form for each ofthe major sections. The balance was assigned to the paging version,in which questions were presented to be visible without scrolling.The instrument contained a maximum of 268 possible questions,including topics that varied in sensitivity and desirability.The survey also permitted comparison of the effect of skip patternsby implementing skip instructions and hyperlinks in the scrollabledesign, and also recorded time at the end of each of the fivetopical sections. Differences between designs are evaluatedin terms of various forms of nonresponse, univariate and bivariatemeasurement properties, and proxies for respondent burden.     

FM local newscasts in the Southwest: A disappearing service

This 2004 investigation of FM radio stations in seven southwestern states presents a snapshot of where radio news might be heading early in our new millennium. Radio is rarely the topic of discussion, giving it the dubious identity of the “forgotten medium.” Seven discrete variables in the form of YES|NO questions are formulated from a 1993 to 2004 literature review that takes into account the demise of radio news on the FM dial. An e-mail questionnaire was answered by management at N = 61 FM stations regarding newscasts in their daily programming. The picture for radio news on the FM dial is gloomy as budget cuts and consolidations impact the newsroom.     

Common pitfalls of beginning therapists utilizing enactments

Empirical data, clinical observation, and theoretical rationales support use of enactments as a fundamental mechanism of change in relationship therapies. Yet beginning therapists may lack an adequate conceptual framework and operational training essential to effectively utilize enactments. Inadequate training may contribute to ineffective execution, and in turn to negative results, which could lead to abandonment of enactments. This study sought to identify proficiencies and nonproficiencies of beginning therapists in conducting enactments. Twenty beginning therapists from three Commission on Accreditation for Marriage and Family Therapy Education (COAMFTE)-accredited programs were briefly trained in an indirect therapy style that incorporates enactments. Twenty-six therapist enactments were coded using a comprehensive observational measure designed to assess proficiencies and nonproficiencies in executing enactment phases, component tasks, and subcomponent operations. Results suggest that beginning therapists struggle with numerous clinical operations conceptually linked to the successful engagement of relationships in marriage and family therapy. In light of these findings, specific recommendations for additional enactment training in COAMFTE-accredited programs are offered.