Dimensions Of Heterogeneity Research Articles

Pay, Employment, and Dynamics of Young Firms

Why do young firms pay less? Using confidential microdata from the US Census Bureau, we find lower earnings among workers at young firms. However, we argue that such measurement is likely subject to worker and firm selection. Exploiting the two-sided panel nature of the data to control for relevant dimensions of worker and firm heterogeneity, we uncover a positive and significant young-firm pay premium. Furthermore, we show that worker selection at firm birth is related to future firm dynamics, including survival and growth. We tie our empirical findings to a simple model of pay, employment, and dynamics of young firms.

Carpooling with heterogeneous users in the bottleneck model

We investigate the effects of carpooling in a dynamic equilibrium model of congestion, which captures various dimensions of heterogeneity: heterogeneity in the preference for and cost of carpooling, heterogeneity in values of time and values of schedule delay. We investigate various policy scenarios: no-toll, first-best pricing, and subsidization of carpooling. The optimally differentiated subsidy equals each type of users’ marginal external benefit (MEB) of switching to m-person carpooling or carpooling, which turns out to be heterogeneous for “ratio heterogeneity”, where the ratios of the values of time and schedule delay vary, and homogeneous for “proportional heterogeneity”, where these values vary in fixed proportion over the population. If such differentiation over users is impossible, the subsidy is a weighted average of the MEB’s, with the weights reflecting the relative sensitivity of the group size of carpoolers to the subsidy. Using a numerical example, we investigate the welfare effects and distributional effects of different policies. The relative efficiency of the differentiated subsidization first increases and then falls with the degree of ratio heterogeneity, and decreases over the entire parameter range and more with the degree of proportional heterogeneity.

Identifying Multi-Attribute Hedonic Models

This paper derives conditions under which preferences and technology are nonparametrically identified in hedonic equilibrium models, where products are differentiated along more than one dimension and agents are characterized by several dimensions of unobserved heterogeneity. With products differentiated along a quality index and agents characterized by scalar unobserved heterogeneity, single crossing conditions on preferences and technology provide identifying restrictions. We develop similar shape restrictions in the multi-attribute case and we provide identification results from the observation of a single market. We thereby extend identification results in Matzkin (2003) and Heckman, Matzkin, and Nesheim (2010) to accommodate multiple dimensions of unobserved heterogeneity.

Household wealth and gender gap widening in height: Evidence from adolescents in Ethiopia, India, Peru, and Vietnam

This study investigates the relationship between household wealth and child height utilizing longitudinal data on 7150 children from Ethiopia, India, Peru, and Vietnam. The concept of conditional wealth is applied to separate the influence of wealth in early childhood. Conditional wealth is the change in wealth that was unpredicted at the age of 5 years. This study finds two dimensions of heterogeneity in the wealth-gradient of adolescent height: gender and stunting status at the age of 5 years. For all four countries in the study, the effect of conditional wealth on adolescent height is stronger for boys than for girls. The estimates for the pooled sample indicate that after the age of 5 years, the growth of children who were stunted at that age is significantly more responsive to conditional wealth than the growth of non-stunted children. The analysis results show that for boys in Ethiopia, a one-standard-deviation increase in preadolescence wealth is associated with an increase of 1 cm (standard error [SE]: 0.3) in height at the age of 15 years. For boys in the Indian state of Andhra Pradesh, Peru, and Vietnam, the corresponding figures are 1.1 cm (SE: 0.4), 1.8 cm (SE: 0.4), and 1.2 cm (SE: 0.4), respectively. The effect of preadolescence wealth on adolescent height is not statistically significant for girls, except in some regions. Overall, the results suggest that household wealth in preadolescence disproportionately benefits the male population in these countries when using height as a proxy for health.

Self-Assessed Financial Literacy in Housing Markets

This paper introduces a novel dimension of household heterogeneity that plays an important role in housing markets. Households who self-assess themselves to be more financially literate are 1) more likely to own a house and 2) take on higher leverage on their home. We solve a heterogeneous agent portfolio choice model to infer the role of mortgage terms and of expectations on future house prices for the empirical patterns. We find that households with higher levels of self-assessed financial literacy are in fact better at the parts of the transaction that are relevant to them, namely access to more accommodating mortgage terms when they are young and better risk-return trade-offs when they are old. Moreover, by ignoring heterogeneity in financial literacy, standard models introduce quantitatively substantial biases in evaluating housing market policies. Housing demand elasticity with respect to wealth is downsized by approximately 40% when taking financial literacy into account.

Beyond position-awareness—Extending a self-adaptive fall detection system

Ambient Assisted Living using mobile device sensors is an active area of research in pervasive computing. Multiple approaches have shown that wearable sensors perform very well and distinguish falls reliably from Activities of Daily Living. However, these systems are tested in a controlled environment and are optimized for a given set of sensor types, sensor positions, and subjects. We propose a self-adaptive pervasive fall detection approach that is robust to the heterogeneity of real life situations. Using the data of four publicly available datasets, we show that our system is not only robust regarding the different dimensions of heterogeneity, but also adapts autonomously to spontaneous changes in the sensor’s position at runtime. In this paper, we extend our self-adaptive fall detection system with (i) additional algorithms for fall detection, (ii) an approach for cross-positional sensor fusion, (iii) a fall detection approach that relies on outlier detection, and (iv) a smart fall alert. Additionally, we present implementation and evaluation of these extensions.

The Investigation and Study of the Cross-Culture Social Adaption of Students from ASEAN in Jiangxi Province

The social network of foreign students and its heterogeneity are the important factors that influence the cross-cultural adaptation of international students. In this paper, some colleges and universities in Nanchang ASEAN students studying design as an example, the heterogeneity of the questionnaire of social network, analyzes the social network heterogeneity present situation, then using two element Logistic regression analysis to examine various dimensions of heterogeneity affect cross-cultural adaptation. At last, drawing conclusions and recommendations for improvement, improving the cross-cultural adaptability of students.

Family Firm Heterogeneity and Tax Avoidance: The Role of the Founder

Family business research suggests that the population of family firms cannot be regarded as a homogenous group. Therefore, with respect to tax avoidance, we analyze the role of the founder as one dimension of family firm heterogeneity. Specifically, we consider socioemotional wealth loss aversion and find that founders may affect the level of tax avoidance not only when they have direct influence (i.e., serving as CEO) but also when they possess solely indirect influence (i.e., having substantial ownership or a seat on the board). Overall, our results suggest that founders remain attached to their firms despite giving up executive positions.

Package Network Model: A Way to Capture Holistic Structural Features of Open-Source Operating Systems

Open-source software has become a powerful engine for the development of the software industry. Its production mode, which is based on large-scale group collaboration, allows for the rapid and continuous evolution of open-source software on demand. As an important branch of open-source software, open-source operating systems are commonly used in modern service industries such as finance, logistics, education, medical care, e-commerce and tourism, etc. The reliability of these systems is increasingly valued. However, a self-organizing and loosely coupled development approach complicates the structural analysis of open-source operating system software. Traditional methods focus on analysis at the local level. There is a lack of research on the relationship between internal attributes and external overall characteristics. Consequently, conventional methods are difficult to adapt to complex software systems, especially the structural analysis of open-source operating system software. It is therefore of great significance to capture the holistic structure and behavior of the software system. Complex network theory, which is adequate for this task, can make up for the deficiency of traditional software structure evaluation methods that focus only on local structure. In this paper, we propose a package network model, which is a directed graph structure, to describe the dependency of open-source operating system software packages. Based on the Ubuntu Kylin Linux Operating system, we construct a software package dependency network of each distributed version and analyze the structural evolution through the dimensions of scale, density, connectivity, cohesion, and heterogeneity of each network.

Foreign Assistance and Emigration: Accounting for the Role of Non-Transferred Aid

Since policymakers increasingly regard foreign aid as a means to manage international flows of migrants, it is important to obtain accurate empirical evidence on the complex link between aid and migration. Recent research has shown that the impact of foreign assistance on migrant flows is highly heterogenous across aid categories. In this paper, we focus on a dimension of heterogeneity that has so far not been considered in the literature, namely whether or not the delivery of foreign aid is associated with a transfer of resources to the recipient country. We show in a first step that non-transferred aid is quantitatively important, accounting for more than 25 percent of overall aid given by OECD DAC donors in 2016. Running separate gravity-type regressions for transferred and non-transferred aid, we then find that transferred aid has a much stronger (negative) impact on migration than the previously used total aid variable that includes the non-transferred component. As may be expected, non-transferred aid itself does not appear to affect migrant flows. A high share of non-transferred aid would therefore be at odds with donors’ stated goal of tackling the root causes of migration.

ChIPmentation for Low-Input Profiling of In Vivo Protein-DNA Interactions.

Many of the key cellular processes including establishing the cell's identity are governed by chromatin proteins. Mapping their binding on the level of a single cell would give us important insights into a new dimension of cellular heterogeneity. However, ChIP-seq, the main method to study protein-DNA interaction in the chromatin context, has proven very challenging to scale down. ChIPmentation is a modification of ChIP-seq, in which the Tn5 transposase is used to introduce sequencing adapters in one step. This allows to significantly reduce the required input material. ChIPmentation is a robust and versatile approach and even though it has not yet achieved single-cell resolution, we believe that it is a very promising starting point for further downscaling.

Adjusting the size of nations: Empirical determinants of separatism and the Soviet breakup

Little is known about the empirical determinants of state formation and dissolution, despite a rich theoretical literature on the subject. This paper exploits large variation in separatist protests across the 183 provinces of the Soviet Union between 1987 and 1992 to measure the demand for autonomy and secession. This enables an investigation into the theoretical prediction that the incentive to separate should be influenced by the trade-off between the size of the potentially separating jurisdiction and preference heterogeneity. I find evidence consistent with the existence of this trade-off: Regions that are more different from the center along some dimension of heterogeneity see a higher incidence of separatist protests per capita. Likewise, proposals to grant autonomy to large jurisdictions attract disproportionately more popular support. These results persist after controlling for various factors influencing general protest turnout, including repression by the authorities.

The effects of social capital on knowledge heterogeneity

PurposeThe purpose of this paper is to examine the influences of social capital on knowledge heterogeneity in order to advance the understanding of the effects and to reconcile existing inconsistent findings.Design/methodology/approachSurvey data collected from 105 new product development (NPD) projects were analyzed with regression-based methods.FindingsThe results indicated that trust, centralization and shared vision as the three social capital dimensions generally have negative impacts on the domain and presentation dimensions of knowledge heterogeneity. However, the three dimensions of social capital do not exhibit consistent influences on the tacitness heterogeneity (i.e. an epistemological dimension of knowledge heterogeneity).Research limitations/implicationsMore research is needed to explore the role of social capital dimensions in developing a range of knowledge attributes of NPD teams, among which knowledge heterogeneity is one. The various dimensions of knowledge an NPD team possesses should have performance implications and deserve future investigation.Originality/valueThe study is one of the first documented attempts to demonstrate contingencies in the relationship between social capital and knowledge heterogeneity. The effect of social capital on knowledge heterogeneity should be understood at the level of dimensions of the two respective constructs.

Family clans and public goods: Evidence from the New Village Beautification Project in South Korea

Ethnic and linguistic heterogeneity are widely studied as determinants of social capital, conflict, and institutional quality. In many cultures, another important dimension of heterogeneity is family clan membership. I study the relationship between family clan diversity in South Korean villages and the voluntary production of public goods and contributions of private resources for village projects. Under the 1970–1971 New Village Beautification Project, the government distributed resources to each village for the production of village public goods. Subsequently, the government systematically evaluated how well these resources were applied. I combine these data with information on village family clan structures collected by the Japanese Colonial Government, as well as records of land donations for village projects between 1970 and 1980. I find an inverted-U-shaped effect of group heterogeneity on the improvement of public goods.

Family Clans and Public Goods: Evidence from the New Village Beautification Project in South Korea

Ethnic and linguistic heterogeneity are widely studied as determinants of social capital, conflict, and institutional quality. In many cultures, another important dimension of heterogeneity is family clan membership. I study the relationship between family clan diversity in South Korean villages and the voluntary production of public goods and contributions of private resource for village projects. Under the 1970-1971 New Village Beautification Project, the government distributed resources to each village for the production of village public goods. Subsequently, the government systematically evaluated how well these resources were applied. I combine these data with information on village family clan structures collected by the Japanese Colonial Government, as well as records of land donations for village projects between 1970 and 1980. I find an inverted-U-shaped effect of group heterogeneity on the improvement of public goods.

Acción colectiva y asociación de heterogeneidades en mercados agroecológicos campesinos: Asoproorgánicos (Cali, Colombia)

En este artículo se analiza la heterogeneidad constitutiva de los mercados agroecológicos campesinos (mac). Esta es valorada como fundamental para la construcción de relaciones entre actores y para la realización de acciones colectivas orientadas a fortalecer la práctica de alimentación agroecológica y a lograr el propósito de “Hambre cero” promulgado en los Objetivos de Desarrollo Sostenible (ods). Se emplea la etnografía multilocal (Marcus, 2001) como enfoque metodológico para estudiar dinámicas microsociales que se producen en los mac y en las fincas de producción agroecológica conectadas con ellos. El mac de Asoproorgánicos en la ciudad de Cali se privilegia como lugar para situar el estudio, en el que se generan datos cualitativos mediante entrevistas y observaciones consignadas en diarios de campo entre octubre del 2015 y noviembre del 2017. Se propone el análisis simétrico de los datos (Rodríguez-Giralt, 2009) para conceptualizar las entidades sociales, naturales y tecnológicas que configuran los mac, como construcciones cuya principal característica es la heterogeneidad que se produce entre ellas (Doménech y Tirado, 1998). Se analizan cuatro dimensiones de la heterogeneidad: a) material, referida a la asociación de entidades humanas y no humanas; b) espacial, como efecto de diferentes modos de practicar el espacio; c) temporal, configurada a partir de tiempos reversibles, irreversibles y narrados; y d) heterogeneidad de poder, asociada con las tensiones y fuerzas mediante las que se regula el colectivo (Mendiola, 2003). Se concluye que el estudio de la heterogeneidad contribuye a la ampliación de repertorios teóricos en ciencias sociales, específicamente en psicología social, y que esta es fundamental para la construcción de relaciones entre múltiples actores. Construir y mantener la asociación de heterogeneidades es una acción que involucra múltiples tensiones, afectos y resultados inesperados, dado que esta no se reduce a una variación de la homogeneidad. Su comprensión puede fortalecer el potencial de los mac para lograr cambios sociales a través de prácticas alimentarias sostenibles y, de este modo, hacer posibles los cursos de acción trazados por los Movimientos Sociales por la Soberanía Alimentaria (mssa).

A Predictive Analytics Understanding of Cooperative Membership Heterogeneity and Sustainability

Recent advances in cooperative theory have focused on membership heterogeneity as being a significant challenge for cooperative sustainability. We use predictive analytics to forecast U.S. farmer cooperative sustainability at an aggregate level and include multiple dimensions of membership heterogeneity. We report the importance and shape of the effect of membership heterogeneity when predicting and forecasting cooperative sustainability in the near-term. We also report forecasts of cooperative sustainability given expected changes to membership heterogeneity. The data this study used are from the United States Department of Agriculture (USDA)-Economic Research Service (ERS) Agricultural Resource Management Survey (ARMS) joined with USDA-Rural Development cooperative financial data at the state level. Membership heterogeneity was found to be less relevant than other variables included in the model for predicting cooperative business volume and number of cooperatives headquartered per state, and an estimate of cooperative sustainability. Membership heterogeneity effects were mostly offsetting given expected changes to member heterogeneity, and/or were offset due to changes to other macro factors. Consequently, we conclude membership heterogeneity may affect the number of cooperatives and extent consistent with theoretical literature at a micro level; however, we also expect a similar level of sustainability of cooperatives at an aggregate level in the near-term despite changes to membership heterogeneity.

Multi‐Omics Factor Analysis—a framework for unsupervised integration of multi‐omics data sets

Multi‐omics studies promise the improved characterization of biological processes across molecular layers. However, methods for the unsupervised integration of the resulting heterogeneous data sets are lacking. We present Multi‐Omics Factor Analysis (MOFA), a computational method for discovering the principal sources of variation in multi‐omics data sets. MOFA infers a set of (hidden) factors that capture biological and technical sources of variability. It disentangles axes of heterogeneity that are shared across multiple modalities and those specific to individual data modalities. The learnt factors enable a variety of downstream analyses, including identification of sample subgroups, data imputation and the detection of outlier samples. We applied MOFA to a cohort of 200 patient samples of chronic lymphocytic leukaemia, profiled for somatic mutations, RNA expression, DNA methylation and ex vivo drug responses. MOFA identified major dimensions of disease heterogeneity, including immunoglobulin heavy‐chain variable region status, trisomy of chromosome 12 and previously underappreciated drivers, such as response to oxidative stress. In a second application, we used MOFA to analyse single‐cell multi‐omics data, identifying coordinated transcriptional and epigenetic changes along cell differentiation.

Price or Variety? An Evaluation of Mergers Effects in Grocery Retailing

Assortment decisions are key strategic instruments for firms responding to local market conditions. We assess this claim by studying the effect of a national merger between two large Dutch supermarket chains on prices and on the depth as well as composition of assortment. We adopt a difference-in-differences strategy that exploits local variation in the merger’s effects, controlling for selection on observables when defining our control group through a matching procedure. We show that the local change in competitive conditions due to the merger did not affect individual products’ prices but it led the merging parties to reposition their assortment and increase average category prices. While the low-variety and low-price target’s stores reduced the depth of their assortment when in direct competition with the acquirer’s stores, the latter increased their product variety. By analyzing the effect of the merger on category prices, we find that the target most likely dropped high priced products, while the acquirer added more of them. Thus, the merging firms reposition their product offerings in order to avoid cannibalization and lessen local competition. Further, we show that other dimensions of heterogeneity, such as market concentration, whether a divestiture was imposed by the Dutch competition authority, and the re-branding strategy of the target stores, are important for explaining the post-merger dynamics. A simple theoretical model of local-market variety competition explains most of our findings.

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