Detecting structural change with heteroskedasticity

The hypothesis of structural stability that the regression coefficients do not change over time is central to all applications of linear regression models. It is rather surprising that existing theory as well as practice focus on testing for structural change under homoskedasticity – that is, regression coefficients may change, but the variances remain the same. Since structural change can, and often does, involve changes in variances, this is a puzzling gap in the literature. Our main focus in this paper is to utilize a newly developed test (MZ) by Maasoumi et al. (2010 Maasoumi, E., Zaman, A., Ahmed, M. (2010). Tests for structural change, aggregation, and homogeneity. Econ Model. 27(6):1382–1391.[Crossref], [Web of Science ®] , [Google Scholar]) that tests simultaneously for break in regression coefficients as well as in variance. Currently, the sup F test is most widely used for structural change. This has certain optimality properties shown by Andrews (1993 Andrews, D.W.K. (1993). Test for parameter instability and structural change with unknown change point. Econometrica. 61(4):821–856.[Crossref], [Web of Science ®] , [Google Scholar]). However, this test assumes homoskedasticity across the structural change. We introduce the sup MZ test which caters to unknown breakpoints, and also compare it to the sup F. Our Monte Carlo results show that sup MZ test incurs only a low cost in case of homoskedasticity while having hugely better performance in case of heteroskedasticity. The simulation results are further supported by providing a real-world application. In real-world datasets, we find that structural change often involves heteroskedasticity. In such cases, the sup F test can fail to detect structural breaks and give misleading results, while the sup MZ test works well. We conclude that the sup MZ test is superior to current methodology for detecting structural change.     

Sociotropic Concerns and Support for Counterterrorism Policies*

Objective. An individual's personal experiences and perception of the collective experience are often linked to political attitudes, especially those concerning the national economy. In this article, we examine whether personal concern about terrorism and perceptions of public concern about terrorism affect attitudes about counterterrorism policies. In addition, we evaluate which factor is the strongest predictor across several counterterrorism policies. Method. We analyze individual‐level survey data collected during the fall of 2001. Results. Our results indicate that perceptions of public concerns are the strongest and most consistent predictor of policy attitudes about terrorism. Conclusion. The implications for theory about perceptions of public opinion and the competing role of personal interest and sociotropic concern are discussed.     

Lifting the veil of silence: Jamuna's narrative of pain

This article relates the story of the life of Jamuna, a married mother of two boys and a girl living among a scheduled caste in India. The female researcher had been interviewing Jamuna's husband, who sells excess cloth to wholesalers and is active in the Bahujan Samaj Party, which is seeking to liberate India's lower castes. Jamuna usually ignored the female researcher or treated her curtly. The researcher, however, invited herself to lunch at Jamuna's house one day, and Jamuna unexpectedly began talking about her life while she prepared the food. Jamuna refers to her husband as "Bhim's father" (Bhim is her oldest son). Bhim's father rules the household, controls the money, never consults his wife, and treats her like a servant. Jamuna looks much older than her estimated 25 years. She was engaged when she was 8, never attended school, and was kept indoors. Her children attend an expensive school, and her husband wants them all to stay in school as long as possible and then get jobs. Jamuna was married to Bhim's father because his family did not demand a dowry. Both families have small farms, but her family grows more crops and makes more money. She used to live with her in-laws but now they avoid her. Jamuna feels strongly that girls should be married early to avoid disgrace. Jamuna was shocked by menstruation and intercourse. After her third delivery, Bhim's father allowed her to become sterilized. She hates her husband and believes he hates her. He treats her like a slave and insults her. His only virtue is that he ignores other women. Jamuna has no friends or confidants. She was not consulted about the move from the village to Delhi. When Bhim's father is away, she has to tend to his business and risk his anger over her mistakes. After this outpouring, Jamuna retreated to silence when the interviewer came to visit.     

‘The language is disgusting and they refer to my disability’: the cyberharassment of disabled people

Disabled people face hostility and harassment in their socio-cultural environment. The use of electronic communications creates an online context that further reshapes this discrimination. We explored the experiences of 19 disabled victims of cyberharassment. Five themes emerged from the study: disability and health consequences, family involvement, misrepresentation of self, perceived complexity, and lack of awareness and expertise. Cyberharassment incidents against disabled people were influenced by the pre-existing impairment, perceived hate-targeting, and perpetrators faking disability to get closer to victims online. Our findings highlight a growing issue requiring action and proper support.     

Parental Investments in College and Later Cash Transfers

Parents often provide generous financial transfers to their adult children, perhaps assisting with college expenses, recognizing major life course events, or cushioning against negative financial shocks. Because resources are limited, a transfer made to one child likely affects transfers made to others in the family. Despite such possibilities, data limitations have led previous authors to focus almost exclusively on a single type of transfer made at a single point in time. Using data from the Health and Retirement Study, we examine the relationships among parental transfers for college and later cash transfers to all children within a family. We find that parents typically spend differentially on the postsecondary schooling of their children but find no evidence that this differential spending is offset by later cash transfers.     

Welfare work requirements and child well-being: Evidence from the effects on breast-feeding

A central theme of welfare reform is that recipients are required to engage in work activities. In many states, these work requirements apply to mothers whose children are a few months old, which may increase the costs and decrease the prevalence of breast-feeding. Given the substantial benefits of breast-feeding, any reduction represents an important negative consequence of these requirements. Our results suggest that in the absence of welfare reform, the national breast-feeding rate six months after birth would have been 5.5% higher in 2000. Such negative consequences of these policies must be weighed against potential benefits as states refine their welfare programs.     

CharacteriStics and utilization of midwives in a selected rural area of East Pakistan

The purpose of this study was to obtain information about the utilization of midwives (dais) by village women and to learn more about the characteristics and practices of those dais. Two interview schedules were prepared. The first was used to interview 632 village women to determine who performed or assisted with their last two deliveries. The second was used to obtain information from 21 dais.The results of the first phase may be summarized as follows: (a) 38 per cent of the women were delivered by relatives; (b) 33 per cent of the women delivered their own children; (c) 14 per cent were delivered by neighbors; (d) 6 per cent were delivered by dais; (e) 2 percent were delivered in hospitals; and (f) the remaining 7 per cent were accounted for by several minor categories.The results of the interviews with dais are summarized as follows: (a) they are mainly widows and older women; (b) they have no formal training; (c) they work for friends, neighbors, and relatives and receive a sari as compensation; (d) they cannot handle complicated deliveries; (e) they deliver 3-4 children a year; (f) their sterilizing procedures depend upon soap, water, and folk beliefs; (g) most think midwifery is a worthwhile service; (h) about one-half have a general understanding of the reproduction process; (i) most do not know how to prevent conception; and (j) about half think that it is a good idea to participate actively in a family planning program.     

2010年大选：伊拉克前途命运的转折点

2005年大选之后的经历给伊拉克国内各政治力量留下了深刻教训,他们意识到国家的安全和稳定需要一个有什叶派、逊尼派以及库尔德人代表参加的联合政府。2010年大选产生了一个联合政府,该政府将有机会实现国家统一,并向邻国传递积极的信号,即伊拉克不会对它们产生威胁,同时新政府也将面临巨大挑战。选举产生的政府将承担起领导国家走向主权独立的历史责任,并努力提高伊拉克在该地区的地位和影响力,尤其是在2011年底美军撤出伊拉克之后。2010年12月21日,新内阁获得国民议会投票表决通过,从而开启了多党派联合执政的架构。     

UNMARRIED PARENTHOOD AND REDISTRIBUTIVE POLITICS

Political survey data for nine West European countries show that women have become increasingly left‐wing compared to men, and that this trend is positively correlated with the rise of nonmarriage in these countries. This pattern is mirrored in German longitudinal data (GSOEP), where transitions out of marriage make women, but not men, significantly more left‐leaning. Analysis of public spending data for high‐income OECD countries (1980–1998) suggests that the political impact of nonmarriage extends to the allocation of State resources with increases in nonmarriage first reducing, and then increasing, State redistribution towards children. (JEL: H31, H42, J12, J13)