Can Likert Scales be Treated as Interval Scales?—A Simulation Study

The Likert scale is widely used in social work research, and is commonly constructed with four to seven points. It is usually treated as an interval scale, but strictly speaking it is an ordinal scale, where arithmetic operations cannot be conducted. There are pros and cons in using the Likert scale as an interval scale, but the controversy can be handled by increasing the number of points. Several researchers have suggested bringing the number up to eleven, on the basis of empirical data. In this article the authors explore this rational and share the same view, but simulate artificial data from both symmetrical normal and skewed distributions where the underlying metric is known in advance. Results show that more Likert scale points will result in a closer approach to the underlying distribution, and hence normality and interval scales. To increase generalizability social work practitioners are encouraged to use 11-point Likert scales from 0 to 10, a natural and easily comprehensible range.     

The Role of Parents in Introducing Children to Financial Services: Evidence from Ghana-YouthSave

Financial capability—financial knowledge, skills, and access to financial services—may help smooth transitions to adulthood for youth and is affected by socialization experiences with parents and other family members. Among a sample of youth and their parents enrolled in the YouthSave experiment in Ghana (n?=?4,065), this study examined whether physical access to financial services and/or visiting banks with parents or other family members was associated with youth’s perceptions and understanding of financial institutions. We found a statistically significant association between visiting the bank with a parent or other family member and youth’s attitudes (β?=?1.45, p?<?0.001) and understanding of financial services (β?=?2.96, p?<?0.001), controlling for other factors like household income and assets. Conversely, physical access (distance, travel time) was not associated with financial services attitudes or understanding. Parents may play an important role in introducing their children to financial services. Practitioners and policy makers should consider ways to include parents in efforts to promote financial capability among youth.     

Who is a volunteer? A cultural and temporal exploration of volunteerism

This study’s purpose was to develop a temporal and cultural definition of volunteering in China. Using a comparative mixed-methods approach, N₁ = 218 Chinese students in Hong Kong were surveyed about their perceptions of volunteering. These quantitative data were compared cross-culturally with a sample of adults in the United States who used the same instrument called Who is a Volunteer? Subsequently, N₂ = 40 of these same students voluntarily participated in a series of focus groups, to further explore more in-depth their opinions about volunteering. The main quantitative results revealed that at the extreme ends of the volunteer scale, both the U.S. and Chinese samples could readily distinguish what volunteering was or was not. The more nuanced empirical differences on the scale (24% of the 21 items) were explained either by unique cultural differences, or the longer and more prominent history that volunteering has had in North America versus China. Main qualitative findings revealed additional between-group cultural differences exemplified by (1) a more family-centric and collectivist Chinese culture versus a more individualistic American culture, (2) a role blurring about volunteer activities versus paid work activities, and (3) that both organizational and cultural context must be seriously considered when defining volunteerism. This study adds to the growing definitional literature on this transformational concept and represents the largest comparative empirical investigation on this subject from East Asia.     

基于多源遥感的城市生态用地识别及生态风险评价

随着城市化进程的不断推进、建设用地不断扩张,城市生态空间正处于剧烈变化中。大量具有生态价值和服务功能的土地不断被侵占,以满足暂时的城市建设需求。但从长远来看,这些生态用地的"消失",将不可避免的影响区域生态平衡,给区域经济的健康发展埋下隐患。广州作为华南的中心城市,改革开放以来,大量外来人口涌入,土地利用变化频繁,生态环境的保护面临着巨大压力。因此,本文基于多源遥感数据,利用监督分类法与综合指数法相综合的复合提取方案对2016年广州生态用地进行空间识别,掌握广州市生态用地存量现状。同时,借助生态风险小区和生态风险等景观指数对广州进行了生态风险评估,结果显示,广州市生态风险呈现明显的多核圈层结构,由多核心的中心向外部逐渐降低。     

Statistical analysis of dependent competing risks model in accelerated life testing under progressively hybrid censoring using copula function

This article considers statistical analysis of dependent competing risks model from Weibull distribution in accelerated life testing, in which copula function is used to examine the dependence structure between competing failure modes. We derive the maximum likelihood estimates, the approximate, and Bootstrap confidence intervals of the parameters. The effects of different dependence structures on the estimates of parameters are investigated. The simulation is given to compare the performance of the estimates when the competing failure modes are dependent with those when the failure modes are independent. Finally, one dataset was used for illustrative purpose in conclusion.     

More on the restricted Liu estimator in the logistic regression model

?iray et al. proposed a restricted Liu estimator to overcome multicollinearity in the logistic regression model. They also used a Monte Carlo simulation to study the properties of the restricted Liu estimator. However, they did not present the theoretical result about the mean squared error properties of the restricted estimator compared to MLE, restricted maximum likelihood estimator (RMLE) and Liu estimator. In this article, we compare the restricted Liu estimator with MLE, RMLE and Liu estimator in the mean squared error sense and we also present a method to choose a biasing parameter. Finally, a real data example and a Monte Carlo simulation are conducted to illustrate the benefits of the restricted Liu estimator.     

Monitoring the coefficient of variation using a variable sample size and sampling interval control chart

This article proposes a CV chart by using the variable sample size and sampling interval (VSSI) feature to improve the performance of the basic CV chart, for detecting small and moderate shifts in the CV. The proposed VSSI CV chart is designed by allowing the sample size and the sampling interval to vary. The VSSI CV chart's statistical performance is measured by using the average time to signal (ATS) and expected average time to signal (EATS) criteria and is compared with that of existing CV charts. The Markov chain approach is employed in the design of the chart.     

Vocational Status,Hukou and Housing Migrants in the New Century: Evidence from a Multi-city Study of Housing Inequality

In the 1960s and 1970s, the countries of Central and Eastern Europe and the Soviet Union experienced an unanticipated stagnation in the process of mortality reduction that was accelerating in the west. This was followed by even starker fluctuations and overall declines in life expectancy during the 1980s and 1990s. We identify statistically the extent to which, since the 1990s, the countries of the post-communist region have converged as a group towards other regional or cross-regional geopolitical blocks, or whether there are now multiple steady-states (‘convergence clubs’) emerging among these countries. We apply a complex convergence club methodology, including a recursive analysis, to data on 30 OECD countries (including 11 post-communist countries) drawn from the Human Mortality Database and spanning the period 1959–2010. We find that, rather than converging uniformly on western life expectancy levels, the post-communist countries have diverged into multiple clubs, with the lowest seemingly stuck in low-level equilibria, while the best performers (e.g. Czech Republic) show signs of catching-up with the leading OECD countries. As the post-communist period has progressed, the group of transition countries themselves has become more heterogeneous and it is noticeable that distinctive gender and age patterns have emerged. We are the first to employ an empirical convergence club methodology to help understand the complex long-run patterns of life expectancy within the post-communist region, one of very few papers to situate such an analysis in the context of the OECD countries, and one of relatively few to interpret the dynamics over the long-term.     

Effects of Parental Divorce on Teenage Children’s Risk Behaviors: Incidence and Persistence

It is generally difficult to separate the effects of divorce from selection when analyzing the effects of parental divorce on children’s risk behaviors. We used propensity score matching and longitudinal data methods to estimate the effects of parents’ divorce on their children’s binge drinking, alcohol consumption, tobacco use, marijuana use, and hard drug use. The children were between 12 and 18 years old in the first survey and between 18 and 24 years old in the second survey. Our results suggest that parental divorce significantly increased the probability of risk behaviors in their children. Moreover, many of these adverse impacts persisted over time, especially among teenage girls.