The triggers of local and distant search: Relative magnitude and persistence in explaining acquisition relatedness

Research on problemistic search has assumed negative attainment discrepancy to be the trigger of both local and distant search. Extending this research, we present and compare two additional triggers: (1) relative attainment discrepancy, which reflects how much a firm's attainment discrepancy deviates from its past negative attainment discrepancies; and (2) persistent attainment discrepancy, which reflects how often the firm experiences below-aspirations performance. Our triggers for distant search model a behavioral explanation for the timing and relatedness of acquisitions. We find support for baseline arguments of problemistic search whereby firms increase both industry- and skill-related acquisitions when they perform below aspirations. When they persistently perform below aspirations, however, this likelihood is reduced and firms engage in acquisitions that are more unrelated, thereby providing support for the notion of expanding search boundaries from local to distant search. Of the two triggers of distant search proposed, relative attainment discrepancy does not induce firms to expand search boundaries. Our results indicate that persistent attainment discrepancy is a key construct to consider when studying the expansion of search boundaries.     

A Graphical Tool for Interpreting Regression Coefficients of Trinomial Logit Models

Multinomial logit (also termed multi-logit) models permit the analysis of the statistical relation between a categorical response variable and a set of explicative variables (called covariates or regressors). Although multinomial logit is widely used in both the social and economic sciences, the interpretation of regression coefficients may be tricky, as the effect of covariates on the probability distribution of the response variable is nonconstant and difficult to quantify. The ternary plots illustrated in this article aim at facilitating the interpretation of regression coefficients and permit the effect of covariates (either singularly or jointly considered) on the probability distribution of the dependent variable to be quantified. Ternary plots can be drawn both for ordered and for unordered categorical dependent variables, when the number of possible outcomes equals three (trinomial response variable); these plots allow not only to represent the covariate effects over the whole parameter space of the dependent variable but also to compare the covariate effects of any given individual profile. The method is illustrated and discussed through analysis of a dataset concerning the transition of master’s graduates of the University of Trento (Italy) from university to employment.     

Fast and approximate exhaustive variable selection for generalised linear models with APES

We present APproximated Exhaustive Search (APES), which enables fast and approximated exhaustive variable selection in Generalised Linear Models (GLMs). While exhaustive variable selection remains as the gold standard in many model selection contexts, traditional exhaustive variable selection suffers from computational feasibility issues. More precisely, there is often a high cost associated with computing maximum likelihood estimates (MLE) for all subsets of GLMs. Efficient algorithms for exhaustive searches exist for linear models, most notably the leaps‐and‐bound algorithm and, more recently, the mixed integer optimisation (MIO) algorithm. The APES method learns from observational weights in a generalised linear regression super‐model and reformulates the GLM problem as a linear regression problem. In this way, APES can approximate a true exhaustive search in the original GLM space. Where exhaustive variable selection is not computationally feasible, we propose a best‐subset search, which also closely approximates a true exhaustive search. APES is made available in both as a standalone R package as well as part of the already existing mplot package.     

External knowledge search,absorptive capacity and radical innovation in high-technology firms

Open innovation and absorptive capacity are two concepts based on the idea that companies can leverage the knowledge generated externally to improve their innovation performance. The aim of this paper is to analyse the joint effect of open innovation and absorptive capacity on a firm's radical innovation. Open innovation is expressed in terms of external search breadth and depth strategies and absorptive capacity is described by distinguishing between potential and realized absorptive capacity. In order to test our hypotheses, we carried out empirical research in firms operating in high-technology industries. The results indicate that internal routines and processes for absorbing external knowledge help explain radical innovation as they show a significant effect of potential and realized absorptive capacity. Also, there is a moderating effect of absorptive capacity on open innovation. Specifically, potential absorptive capacity exerts a positive effect on the relationship between external search breadth and depth and radical innovation. Realized absorptive capacity moderates the influence of external search breadth. These findings confirm the complementary nature of absorptive capacity and open innovation search strategies on radical innovation.     

The context of employment discrimination: interpreting the findings of a field experiment

Although field experiments have documented the contemporary relevance of discrimination in employment, theories developed to explain the dynamics of differential treatment cannot account for differences across organizational and institutional contexts. In this article, I address this shortcoming by presenting the main empirical findings from a multi‐method research project, in which a field experiment of ethnic discrimination in the Norwegian labour market was complemented with forty‐two in‐depth interviews with employers who were observed in the first stage of the study. While the experimental data support earlier findings in documenting that ethnic discrimination indeed takes place, the qualitative material suggests that theorizing in the field experiment literature have been too concerned with individual and intra‐psychic explanations. Discriminatory outcomes in employment processes seems to be more dependent on contextual factors such as the number of applications received, whether requirements are specified, and the degree to which recruitment procedures are formalized. I argue that different contexts of employment provide different opportunity structures for discrimination, a finding with important theoretical and methodological implications.     

Gender Differences in Union Formation in Mexico: Evidence From Marital Search Models

Although increasingly appreciated for their explanatory power in developed societies, marital search models have yet to be widely applied to developing nations. This article evaluates the applicability of marital search models to marriage timing in Mexico. The analysis compares separate models of union formation for men and women that include individual and marriage market predictors. Results show that union formation is closely linked to the uncertainties surrounding the transition to adulthood and the availability of marriageable partners. Improvements in women's economic position do not diminish the attractiveness of marriage, as female independence arguments would suggest. Instead, they are a central force behind the stability of marriage behavior in Mexico. A central transformation identified in the analysis is the reduction in sex differences in age at marriage as women expand their education and labor force participation.     

Comparison of Four New General Classes of Search Designs

A factor screening experiment identifies a few important factors from a large list of factors that potentially influence the response. If a list consists of m factors each at three levels, a design is a subset of all possible 3 ^m runs. This paper considers the problem of finding designs with small numbers of runs, using the search linear model introduced in Srivastava (1975). The paper presents four new general classes of these 'search designs', each with 2 m −1 runs, which permit, at most, two important factors out of m factors to be searched for and identified. The paper compares the designs for 4 ≤ m ≤ 10, using arithmetic and geometric means of the determinants, traces and maximum characteristic roots of particular matrices. Two of the designs are found to be superior in all six criteria studied. The four designs are identical for m = 3 and this design is an optimal design in the class of all search designs under the six criteria. The four designs are also identical for m = 4 under some row and column permutations.     

基于Delphi的医疗器械商品检索系统设计

分析了采用Delphi6.0编程工具研究并设计的医疗器械商品检索系统，介绍了系统开发的环境特征、数据库应用程序开发步骤及开发过程，包括创建主界面、数据库及编程等，分析了该系统存在的不足及改进措施。     

论奉天当局对朝鲜移民开发水田的政策

朝鲜移民的水田开发，促进了东北地区农业经济的发展。开始之初，奉天当局及东北地区官民对开发水田的朝鲜垦民采取了积极鼓励的政策。《满蒙条约》签订之后，为了控制朝鲜移民的迁入和抵制日本帝国主义利用朝鲜移民对中国的侵略，奉天当局对朝鲜移民采取了限制、取缔的政策，严厉禁止朝鲜移民的土地所有权。     

高速SDRAM控制器设计的FPGA实现

同步动态存储器(SDRAM)控制器通常用有限状态机实现,对于一般的设计方法,由于状态数量多,状态转换通常伴随大的组合逻辑而影响运行速度,因此,SDRAM控制器的速度限制了SDRAM存储器的访问速度。该文从结构优化入手来优化方法,利用状态机分解的思想将大型SDRAM控制状态机用若干小的子状态机实现,达到简化逻辑的目的,不仅提高了速度还节省了资源,对该类大型SDRAM控制器的实现有一定参考意义。