Researchers commonly use co-occurrence counts to assess the similarity of objects. This paper illustrates how traditional association measures can lead to misguided significance tests of co-occurrence in settings where the usual multinomial sampling assumptions do not hold. I propose a Monte Carlo permutation test that preserves the original distributions of the co-occurrence data. I illustrate the test on a dataset of organizational categorization, in which I investigate the relations between organizational categories (such as “Argentine restaurants” and “Steakhouses”). 相似文献
Inter-state disparity has been a perennial feature of Indian agriculture. The study probes if per capita income from agriculture has converged across states and finds evidence in favour of beta convergence. Spatial econometric techniques used indicate significant spatial dependence in agricultural growth. Infrastructure like roads, irrigation, and electricity, diversification in cropping pattern and quality of human capital are found to aid in growth. However, excessive rainfall tends to decrease growth rate in India. The spill-over across states are found to be primarily driven by roads, irrigation and rural literacy and we also find significant impact of spatial income growth providing evidence in favour of agglomeration effects. Hence, investments in human capital, physical infrastructure specially water management and incentives towards growing crops which yield higher returns will aid agriculture growth in India.
Using Hungarian firm-transaction level export data, we show that about one third of firm–destination and about one half of firm–product–destination export spells are short-lived, or temporary, each year. This is in odds with theories where comparative advantage is stable and market entry costs are sunk. We show how endogenous choice between variable and sunk cost trade technologies can explain the empirical importance and some characteristics of temporary trade. We build a model in which the likelihood of temporary trade depends on productivity and capital cost of the firm as well as well-known gravity variables of destinations. These predictions are borne out by the data; the likelihood of permanent trade, defined by a simple filter, rises with firm productivity, financial stability, proximity and GDP of destination countries. 相似文献
Migration is a risky behaviour because of the uncertainty about future wages, living conditions, changing relationships with family and friends and cultural adjustment. While there has been some research on risk and uncertainty in migration, this has mostly been approached as a form of ‘rational’ decision-making: such approaches explain why some groups of individuals are more likely than others to migrate, but are limited in explaining individual variations in behaviour within these groups. Individual migrants vs. non-migrants are self-selected in terms of tolerance of risk and uncertainty but, with very few exceptions, there has been no research on migration within the framework of risk tolerance/aversion and competence to manage risk. Moreover, existing research is based on, and constrained by the limitations of, incumbent data-sets. Drawing on a specially commissioned large-scale survey of the UK population, this paper uses principal component analysis and logistic regression to analyse the extent to which risk and risk-related measures can be used to predict four different types of mobility profiles. There are significant associations between these individual mobility characteristics and general risk/uncertainty tolerance, and competence-based tolerance. These are strongest in terms of the two most polarised mobility types: the least mobile, the Stayers, and the most mobile, the Roamers. Recognising that previous migration is exogenous, a further analysis of migration intentions, with previous migration included as an independent variable, finds the propensity for future migration is, in fact, negatively associated with previous migration, probably due to the importance of ‘pure risk’ as opposed to acquired competence via migration experience, and to life cycle considerations. 相似文献
This paper investigates generational differences in the relations between psychological contract fulfillment and work attitudes. Data were collected from a sample of 909 employees in the Dutch service sector. Structural equation modeling analyses were used to test the moderating effects of generational differences on the influence of psychological contract fulfillment on affective commitment and turnover intention. The relationship between psychological contract fulfillment and these work outcomes was moderated by generational differences. Furthermore, results indicate that different generations respond differently to different aspects of psychological contract fulfillment, such as career development, job content, organizational policies, social atmosphere and rewards. The study provides evidence that generational differences impact the reciprocal relationship between employer and employee. Results from this study suggest that Baby Boomers and Generation X may be more motivated by social atmosphere, whereas Generation Y may be more motivated by job content and career development. Fair organizational policies are particularly motivating to Generation X, and providing rewards, though more important to Generation Y, seem mostly unrelated to work outcomes. This article is the first to study the moderation of generational differences in the relationships between psychological contract fulfillment and work outcomes. 相似文献
This paper studies the impact of the recent weakening of Poland's fully funded defined contribution second pension pillar on (i) the long-term sustainability (the deficit and implicit debt) of the full pension system and (ii) the implications for pension benefits (gross replacement rates). Simulation results, based on a stylised version of the Polish pension system, show that, in the baseline scenario, the weakening of the second pillar would permanently lower future pension system debt, chiefly as a result of a cut in replacement rates. But using a combination of pessimistic assumptions including strong population ageing, low real wage growth and an indexation of existing pension benefits on nominal wage growth rather than inflation coupled with bringing in tax expenditures related to the third voluntary pension pillar and an increase in the share of minimum pensioners leads to higher pension system deficits and eventually more public debt at a very long horizon. The simulation results also suggest that if Poland had not transformed its pay-as-you-go first pension pillar into a defined contribution from a defined benefit system, the weakening of the second pillar would deteriorate fiscal sustainability relatively quickly in the baseline scenario. This result suggests that the Hungarian pension reversal would reduce deficit and debt only temporarily, mainly because of Hungary's costly defined benefit first pension pillar: the weakening of the second pillar is tantamount to swapping low current replacement rates (in the defined contribution second pillar) against high future replacement rates in the defined benefit first pension pillar. 相似文献
We develop a model of consulting (advising) where the role of the consultant is to reveal signals to her client that refine the client's original private estimate of the profitability of a project. Although the client can perfectly observe and evaluate these signals, the consultant may only be able to do the same imperfectly, or not at all. This captures the idea that the expert may not fully understand the impact of her advice on the client. We characterize the optimal contract between the consultant and her client. It is a menu consisting of pairs of transfers specifying payments between the two parties in case the project is undertaken by the client and in case it is not. The main result of the article is that in the optimal mechanism, the consultant obtains the same profit as though she could perfectly observe and evaluate the impact of the signals whose release she controls on the client's profit estimate.相似文献