R-optimal designs for multi-factor models with heteroscedastic errors

In this paper, we consider the R-optimal design problem for multi-factor regression models with heteroscedastic errors. It is shown that a R-optimal design for the heteroscedastic Kronecker product model is given by the product of the R-optimal designs for the marginal one-factor models. However, R-optimal designs for the additive models can be constructed from R-optimal designs for the one-factor models only if sufficient conditions are satisfied. Several examples are presented to illustrate and check optimal designs based on R-optimality criterion.     

Organizational Socialization and Psychological Contract: the Vulnerability of Temporary Newcomers. A Case Study from an Italian <Emphasis Type="Italic">Call Center</Emphasis>

This study aims to analyze the link between the construction of an effective psychological contract with the organization and the success of the socialization process. To this purpose 241 employees of a Call Center organization have been contacted. A questionnaire composed by measures of Organizational Socialization (Haueter et al. Journal of Vocational Behavior, 63, 20–39, 2003), Psychological Contract (Rousseau 1995), Job Satisfaction (Wanous et al. Journal of Applied Psychology, 82, 247–252, 1997) and Organizational Committment (Allen and Meyer 1990) was administered. Results have underlined that organizational socialization may influence the development of the psychological contract thus determining job satisfaction and organizational commitment. This research has been developed in an interdisciplinary perspective, taking into account the peculiarity of the Italian legal framework. In this regard, the analysis has been focused on how the E.U. flexicurity strategy has been implemented in Italy, according to the recent reform of labour market regulation (2012–13) and on the specific regulations introduced for call centres.     

The impact of mindful organizing on operational performance: An explorative study

This study explores the effect of Mindful Organizing, a concept originally developed in the high-reliability organizations literature. We show that mindful organizing can also be applied to ordinary organizations seeking better performance, not just to organizations seeking high reliability. Results of this study demonstrate that mindful organizing and operational performance are positively related. Further, mindful organizing benefits organizations in an uncertain environment more than organizations in a stable environment. Future research avenues of this understudied concept in operations management are discussed.     

Almost sure central limit theorem for the products of <Emphasis Type="Italic">U</Emphasis>-statistics

Let (X _n ) be a sequence of i.i.d random variables and U _n a U-statistic corresponding to a symmetric kernel function h, where h ₁(x ₁) = Eh(x ₁, X ₂, X ₃, . . . , X _m ), μ = E(h(X ₁, X ₂, . . . , X _m )) and ? ₁ = Var(h ₁(X ₁)). Denote \({\gamma=\sqrt{\varsigma_{1}}/\mu}\), the coefficient of variation. Assume that P(h(X ₁, X ₂, . . . , X _m ) > 0) = 1, ? ₁ > 0 and E|h(X ₁, X ₂, . . . , X _m )|³ < ∞. We give herein the conditions under which

$\lim_{N\rightarrow\infty}\frac{1}{\log N}\sum_{n=1}^{N}\frac{1}{n}g\left(\left(\prod_{k=m}^{n}\frac{U_{k}}{\mu}\right)^{\frac{1}{m\gamma\sqrt{n}}}\right) =\int\limits_{-\infty}^{\infty}g(x)dF(x)\quad {\rm a.s.}$

for a certain family of unbounded measurable functions g, where F(·) is the distribution function of the random variable \({\exp(\sqrt{2} \xi)}\) and ξ is a standard normal random variable.

     

Multivariate saddlepoint tests on the mean direction of the von Mises–Fisher distribution

This article provides P values for two new tests on the mean direction of the von Mises–Fisher distribution. The test statistics are obtained from the exponent of the saddlepoint approximation to the density of M-estimators, as suggested by Robinson et al. (Ann Stat 31:1154–1169, 2003). These test statistics are chi-square distributed with asymptotically small relative errors. Despite the high dimensionality of the problem, the proposed P values are accurate and simple to compute. The numerical precision of the P values of the new tests is illustrated by some simulation studies.     

Freedom and gross in-migration: an empirical study of the post-great recession experience

Determinants of migration, including policy variables such as tax rates, have been extensively studied by regional scientists over the past several decades. The development of the Economic Freedom of North America Index has allowed researchers to test the relationship between migration patterns and economic freedom, with recent studies finding that net in-migration is positively related to economic freedom. Using a new cross-section measure of economic and personal freedom at the state level, we investigate the relationship between gross in-migration and economic freedom on the one hand and then between gross in-migration and total freedom on the other hand. This empirical study of domestic U.S. migration during the post-Great Recession period finds clear evidence that migrants prefer to move to those states affording higher levels of economic freedom and higher levels of total freedom.     

Dispersive ordering of fail-safe systems with heterogeneous exponential components

Let X ₁, . . . , X _n be independent exponential random variables with respective hazard rates λ₁, . . . , λ _n , and Y ₁, . . . , Y _n be independent and identically distributed random variables from an exponential distribution with hazard rate λ. Then, we prove that X _2:n , the second order statistic from X ₁, . . . , X _n , is larger than Y _2:n , the second order statistic from Y ₁, . . . , Y _n , in terms of the dispersive order if and only if

$\lambda\geq \sqrt{\frac{1}{{n\choose 2}}\sum_{1\leq i < j\leq n}\lambda_i\lambda_j}.$

We also show that X _2:n is smaller than Y _2:n in terms of the dispersive order if and only if

$ \lambda\le\frac{\sum^{n}_{i=1} \lambda_i-{\rm max}_{1\leq i\leq n} \lambda_i}{n-1}. $

Moreover, we extend the above two results to the proportional hazard rates model. These two results established here form nice extensions of the corresponding results on hazard rate, likelihood ratio, and MRL orderings established recently by Pǎltǎnea (J Stat Plan Inference 138:1993–1997, 2008), Zhao et al. (J Multivar Anal 100:952–962, 2009), and Zhao and Balakrishnan (J Stat Plan Inference 139:3027–3037, 2009), respectively.

     

A Cramér-type large deviation theorem for sums of functions of higher order non-overlapping spacings

Let U ₁, U ₂, . . . , U _n–1 be an ordered sample from a Uniform [0,1] distribution. The non-overlapping uniform spacings of order s are defined as \({G_{i}^{(s)} =U_{is} -U_{(i-1)s}, i=1,2,\ldots,N^\prime, G_{N^\prime+1}^{(s)} =1-U_{N^\prime s}}\) with notation U ₀ = 0, U _n = 1, where \({N^\prime=\left\lfloor n/s\right\rfloor}\) is the integer part of n/s. Let \({ N=\left\lceil n/s\right\rceil}\) be the smallest integer greater than or equal to n/s, f _m (u), m = 1, 2, . . . , N, be a sequence of real-valued Borel-measurable functions. In this article a Cramér type large deviation theorem for the statistic \({f_{1,n} (nG_{1}^{(s)})+\cdots+f_{N,n} (nG_{N}^{(s)} )}\) is proved.     

A new measure of association between random variables

We propose a new measure of association between two continuous random variables X and Y based on the covariance between X and the log-odds rate associated to Y. The proposed index of correlation lies in the range [\(-1\), 1]. We show that the extremes of the range, i.e., \(-1\) and 1, are attainable by the Fr\(\acute{\mathrm{e}}\)chet bivariate minimal and maximal distributions, respectively. It is also shown that if X and Y have bivariate normal distribution, the resulting measure of correlation equals the Pearson correlation coefficient \(\rho \). Some interpretations and relationships to other variability measures are presented. Among others, it is shown that for non-negative random variables the proposed association measure can be represented in terms of the mean residual and mean inactivity functions. Some illustrative examples are also provided.     

Bayesian estimation based on ranked set sample from Morgenstern type bivariate exponential distribution when ranking is imperfect

In this paper we consider Bayes estimation based on ranked set sample when ranking is imperfect, in which units are ranked based on measurements made on an easily and exactly measurable auxiliary variable X which is correlated with the study variable Y. Bayes estimators under squared error loss function and LINEX loss function for the mean of the study variate Y, when (X, Y) follows a Morgenstern type bivariate exponential distribution, are obtained based on both usual ranked set sample and extreme ranked set sample. Estimation procedures developed in this paper are illustrated using simulation studies and a real data.     

Institutional convergence: exit or voice?

There is a small but growing literature on the determinants of economic freedom. This paper contributes to this literature in two ways. First, it is empirically shown that β-convergence in economic freedom occurred from 1980 to 2010. Countries with low levels of economic freedom in 1980 “catch up” at a rate of 0.7 percent a year on average, ceteris paribus. Second, the structural characteristics that contribute to this institutional convergence are documented. Conditional convergence estimates suggest democratic institutions do not con- tribute to conditional convergence. Exitability, a variable that captures how easy it is for citizens to “vote with their feet” is related to the change in economic freedom from 1980 to 2010 in a statistically significant manner across all specifications. This provides some preliminary evidence as to the importance of “exit” versus “voice” with respect to the question of institutional change.     

Network design in games with spillovers

How should an organization be designed in order to provide its members with minimal incentives to defect? And how does the optimal design depend on the type of strategic interaction between defectors and remaining organizational members? This paper addresses such issues in a game theoretic model of cooperation, in which an organization is formally represented by a connected network, and where gains from cooperation are given by a partition function. We show that critical structural features of the organization depend in a clear-cut way on the sign of spillovers. In particular, positive spillovers favor the adoption of dispersed and centralized forms, while negative spillovers favor cohesive and horizontal ones. Moreover, if the organizational form determines all the communication possibilities of members, a highly centralized organization—the star—emerges under positive spillovers, whereas two horizontal architectures—the circle and the complete—emerge under negative spillovers.     

On the welfare effects of affirmative actions in school choice

Recent evidence, from both academia and practice, indicates that implementing affirmative action policies in school choice problems may induce substantial welfare losses on the intended beneficiaries. This paper addresses the following two questions: what are the causes of such perverse consequences, and when we can effectively implement affirmative action policies without unsatisfactory outcomes. Using the minority reserve policy in the student optimal stable mechanism as an example, I show that two acyclicity conditions, type-specific acyclicity and strongly type-specific acyclicity, are crucial for the effective implementations of minority reserve policies. I further illustrate how restrictive these two acyclicity conditions are, and the intrinsic difficulty of embedding diversity goals into stable matching mechanisms. Under some regularity conditions, I demonstrate that the minority reserve policy is very unlikely to cause welfare losses on any minority students when the number of schools is sufficiently large.     

Economics of evaluation (with special reference to promotion and tenure committees)

Previous research suggests that universities that fear tenuring bad candidates more than they fear rejecting good candidates would optimally have both department and outside evaluating committees. I find that a higher relative cost of accepting bad candidates is neither necessary nor sufficient for the optimality of more than one committee. Also, with some probability, t, the administration will tenure one with split recommendations from two committees, if one committee is more accurate than the other, one structure will have fewer errors of both types for some range of t, and possibly a lower expected loss from errors for all t.     

Unbiased estimates for a lognormal regression problem and a nonparametric alternative

Given a normal sample with means \({{\bf x}_{1}^{\prime} {\bf \varphi}, \ldots, {\bf x}_{n}^{\prime} {\bf \varphi}}\) and variance v, minimum variance unbiased estimates are given for the moments of L, where log L is normal with mean \({{\bf x}^{\prime} {\bf \varphi}}\) and variance v. These estimates converge to wrong values if the normality assumption is false. In the latter case estimates based on any M-estimate of \({{\bf \varphi}}\) are available of bias \({O\left(n^{-1}\right)}\) and \({O\left(n^{-2}\right)}\). More generally, these are given for any smooth function of \({\left({\bf \varphi}, F\right)}\), where F is the unknown distribution of the residuals. The regression functions need not be linear.     

The changing role of network ties and critical capabilities in an international new venture’s early development

The importance of networks for firm internationalization has been pointed out for several decades. Especially for small and new firms, networks have been found to be an important tool to gain access to resources and to overcome liabilities of newness, smallness and foreignness. Yet, there is a lack of understanding regarding which types of capabilities are developed through networking and how and when networks are used. The aim of this article is to explore how and when different networking activities develop critical capabilities during different phases of an international new venture’s early development. The article is based on a longitudinal, in-depth case study of a Swedish international new venture from the medical-technology industry. We find that the development process is greatly affected by how the individual key actors leverage their network ties to develop critical capabilities – they use existing network ties and different indirect ties during the pre-founding, start-up and establishment of production phases. During the commercialization and sales growth phases, however, many new network ties are developed. The heterogeneity of the individual actors’ backgrounds plays an important role during the different developmental phases. We conclude by advancing a number of propositions in relation to how critical capabilities are developed through networking during different developmental phases.     

Coordination in the El Farol Bar problem: The role of social preferences and social networks

In this paper, we continue the pursuit of the self-coordination mechanism as studied in the El Farol Bar problem. However, in addition to efficiency (the optimal use of the public facility), we are also interested in the distribution of the public resources among all agents. Hence, we consider variants of the El Farol Bar problem, to be distinguished from many early studies in which efficiency is the only concern. We ask whether self-coordinating solutions can exist in some variants of the El Farol Bar problem so that public resources can be optimally used with neither idle capacity nor congestion being incurred and, in the meantime, the resources can be well distributed among all agents. We consider this ideal situation an El Farol version of a “good society”. This paper shows the existence of a positive answer to this inquiry, but the variants involve two elements, which were largely left out in the conventional literature on the El Farol Bar problem. They are social networks and social preferences. We first show, through cellular automata, that social networks can contribute to the emergence of a “good society”. We then show that the addition of some inequity-averse agents can even guarantee the emergence of the “good society”.     

Evaluating corruption under the application of the SOCIO-economic development desgrowth index (Ð-index): the case of Guatemala

Getting a clear sense of the intensity and dynamics of corruption in a society or country is a critical platform for economic growth and development. This paper sets out to bring clarity to the study of corruption through an alternative approach. It examines and demonstrates how corruption can be evaluated by basically hinging it on the socio-economic development deaccumulation that any country can experience in different historical periods. The paper presents the socio-economic development desgrowth index (Ð-index), a new indicator with a complete set of mathematical tools that capture and calculate all the aspects that encompass corruption within a system or country. The paper successfully applied the (Ð-index) to X-ray the successive administrations of Guatemala from 1986 to year 2016 from where we convincingly observed the highs and lows in the corruption dynamics of Guatemala.     

A review of integrated QCA and statistical analyses

Systematically combining quantitative and qualitative research approaches offers the potential for a more comprehensive and nuanced understanding of social scientific phenomena. With their strong opportunities for building, qualifying, and testing social scientific theories, methodological integrations thus enable researchers to make substantive contributions that would not have been possible with one method alone. In this article we demonstrate how the integration of Qualitative Comparative Analysis (QCA) and conventional statistical analysis offers researchers new opportunities for contributing to the social sciences. Whereas statistical analysis is variable-oriented and relies on correlational analysis to make comparisons across cases, QCA is based on set theory, is case oriented, and relies on Boolean algebra to make comparisons between cases. Drawing on the literature on the interdependency between theoretical contribution and methodology, we review studies that integrate QCA and statistical analysis to explain how the specific combination of these two approaches allows researchers to strengthen the theoretical contribution of their research. From our review we identify common challenges and provide solutions for integrating QCA and statistical analysis.