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251.
This paper examines the past transition from low to high fertility which, in Indonesia as elsewhere, preceded the return to lower birth rates. Data from two parts of the island of Sulawesi where fertility rose during the colonial period are used to explain both why it rose, and why it was originally low. Economic conditions, it is argued, were the most important factors, affecting fertility via the supply of income and the demand for labour. Two schematic models of the 'first fertility transition' are proposed. In areas with low population densities and area-extensive forms of agriculture responsive to commercial stimuli, birth rates rose as the growth of commerce raised levels of prosperity, facilitated marriage, and undermined institutions such as debt-slavery which had previously acted to restrict marital fertility. In densely populated areas with labour-intensive agriculture and heavy state taxation in labour, fertility rose in response to demands for women's (and possibly child) labour that did not necessarily lead to gains in income.  相似文献   
252.
253.
This paper investigates the nature of optimal prices for a durable good in the presence of continuous quality improvements. The analysis of optimal prices is based on a nonlinear dynamic model of sales response that relates price, quality, average life of a product and the persistence of quality perceptions. Numerical solutions to the model are derived by employing the generalized reduced gradient algorithm. The results show that optimal price depends on the persistence of quality perceptions and the average life of a product (an aspect of quality). The analysis of optimal results affirms results based on other models and provides insights on the influence that quality has on optimal pricing. The implications of the results and suggestions for future research are discussed.  相似文献   
254.
Most models of investor behavior assume a time-state independent utility function and result in a deterministic solution where a given set of inputs uniquely specifies the decision. In contrast, a state preference model using a time-state dependent utility function is derived in this paper. The model allows the investment choice decision to be analyzed in a game theoretic context. The general solution is a mixed strategy which allows for a probabilistic interpretation of the decision. The approach presented in this paper can accommodate anomalies such as intransitivity of preference and satisficing as rational behavior. An example of a possible implementation is given along with interpretations of the outcomes.  相似文献   
255.
Decision makers often face scheduling problems in which processing times are not known with certainty. Non-regular performance measures, in which both earliness and tardiness are penalized, are also becoming more common in both manufacturing and service operations. We model a managerial environment with task processing times (which include sequenceindependent set-up times) prescribed by three-parameter lognormal distributions. Upon completion, each task derives a reward given by a particular piecewise-linear reward function. The objective is to select a sequence of tasks maximizing the expected total reward. The relative generality of the problem renders many enumerative methods inapplicable or computationally intractable. To overcome such difficulties we develop efficient priorityinduced construction (PIC) heuristics which build up a complete schedule by inserting tasks (singly from a list) into a partial sequence of tasks. In each partial and complete sequence a period of idle time is permitted prior to the first task. Performance on realistic-sized problems is very encouraging, with cost penalties averaging less than one percent.  相似文献   
256.

Studies of economic insecurity tend to focus on changes in incomes and transitions in and out of income poverty. Yet family economic conditions are shaped by more than just income. Levels of assets and wealth, and changes in these over time also play a role. To identify which groups of the poor have been structurally trapped in poverty over time, using the Korean Welfare Panel Study, we examined the dynamics of asset poverty from 2005 to 2014. We defined three asset poverty lines by operationalizing assets as resources for either future consumption or development. Findings show that asset poverty experience in a previous year significantly increased the probability to incur asset poverty by 5–12% for all analysis samples. In addition, the probability of incurring asset poverty decreased with home ownership, higher disposable income, and greater diversification of the household portfolio. Our findings suggest that the asset poor are likely to fall into structural and persistent poverty over time, and an asset-building approach is needed to improve the asset poverty status of households in South Korea.

  相似文献   
257.
This review examines the current published and “grey” literature relating to the experiences of homelessness by people seeking asylum within Australia. While many people seeking asylum have experienced homelessness during their flight, inadequate and unaffordable housing are a feature of the settlement experience for a large number of new arrivals to Australia, putting at risk their successful settlement. This study aims to explore the factors influencing access to stable housing. A systematic review of the academic literature and a search of the grey literature identified 11 articles and 20 documents related to homelessness and people seeking asylum in Australia. The academic literature included a variety of methods and approaches to the investigation of the experience of homelessness in Australia. The grey literature was more practice based, including evaluation and research reports, submissions, and newsletters. Findings suggest that experiences of homelessness are multifaceted and have a range of influences, including policy, financial stress, lack of access to education and employment, and a lack of affordable and suitable housing. Any solutions to address homelessness need to be similarly diverse. Discrimination from real estate agents and employers was also identified as a barrier to housing for many people seeking asylum, an issue that will need to be addressed at a systematic level. The lack of research published in the academic literature means that although there may be some programmes or solutions operating in the community, as demonstrated in the grey literature, this information is not being shared beyond organisation websites or subscriber lists, resulting in a lack of coherency or sharing of solutions. This review highlights the need for further attention to the factors influencing homelessness in asylum seekers, the experience of homelessness, and how these can be addressed by government and non-government led strategies and policy development.  相似文献   
258.
259.
The growth in macro-level income inequality in the United States is well established, but less is known about patterns of inequality at subnational scales and how they vary between and within rural and urban localities. Using data from the Decennial Census and American Community Survey, we produce estimates of within-county income inequality from 1970 to 2016 and analyze differences in inequality levels, the persistence of high (low) inequality, and populations' exposure to high (low) inequality across the rural-urban continuum. We find that income inequality has historically been higher in non-metropolitan than metropolitan counties, but inequality levels converged by 2016 due to growing inequality in metropolitan counties. Additionally, levels of inequality were generally persistent within counties over time, except that counties characterized by low inequality in 1970 were unlikely to remain as such in 2016. Third, non-trivial shares of the metropolitan population resided in low-inequality contexts in 1970, but virtually none of the U.S. population resided in such places by 2016. Residence in high-inequality counties is normative in rural and urban America. This statistical analysis provides an updated portrait of income inequality across the rural-urban continuum, and should spur additional research on stratification in rural America during an era of growing inequality.  相似文献   
260.
This study uses Lovejoy and Saxton's (2012) hierarchy of engagement to analyze how nonprofit human service organizations use Facebook and Twitter to engage stakeholders. Their framework has not been applied to this nonprofit subgroup, and most previous scholarship on this topic focuses on just one platform. We also contribute by drawing on organizational theory to better understand variation in the modes of engagement organizations emphasize. Based on our analysis, we add new subcategories to the hierarchy of engagement. In addition, we find that compared to other nonprofit subgroups examined in previous research, the organizations in our sample placed a greater emphasis on using social media messages to ask stakeholders to take action. We report only modest variations in how organizations were using Facebook and Twitter. Finally, according to our results, resource dependence and stewardship theories help explain the modes of engagement organizations prioritize.  相似文献   
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