Reasons That Could Lead People to Divorce in an Evolutionary Perspective: Evidence from Cyprus

In the current research, we aimed to identify the reasons that could drive people to get a divorce. In Study 1, we employed qualitative research methods, and we identified 62 reasons that could potentially drive people to get a divorce. Using quantitative research methods, in Study 2 we classified these reasons into 7 broader factors. We found that being a harmful spouse was the most important factor for divorce, followed by incompatibility and in-law problems. We also found significant sex differences in several factors such as women indicating a higher willingness than men to divorce a harmful spouse. In addition, participants with children were less willing to divorce a harmful spouse than those who had no children. Finally, using second-order principal components analysis, we classified the 7 factors into 2 broader domains of reasons for getting a divorce.     

Approximate maximum likelihood estimation in the presence of extra-poisson variation

A two-stage hierarchical model for analysis of discrete data with extra-Poisson variation is examined. The model consists of a Poisson distribution with a mixing lognormal distribution for the mean. A method of approximate maximum likelihood estimation of the parameters is proposed. The method uses the EM algorithm and approximations to facilitate its implementation are derived. Approximate standard errors of the estimates are provided and a numerical example is used to illustrate the method.     

The relationship between childbearing and transitions from marriage and cohabitation in Britain

In this article, we describe a general framework for the analysis of correlated event histories, with an application to a study of partnership transitions and fertility among a cohort of British women. Using a multilevel, multistate competing-risks model, we examine the relationship between prior fertility outcomes (the presence and characteristics of children and current pregnancy) and the dissolution of marital and cohabiting unions and movements from cohabitation to marriage. Using a simultaneous-equations model, we model these partnership transitions jointly with fertility, allowing for correlation between the unobserved woman-level characteristics that affect each process. The analysis is based on the partnership and birth histories that were collected for the 1958 birth cohort (National Child Development Study) aged 16-42. The findings indicate that preschool children have a stabilizing effect on their parents 'partnership, whether married or cohabiting, but the effect is weaker for older children. There is also evidence that although pregnancy precipitates marriage among cohabitors, the odds of marriage decline to prepregnancy levels following a birth.     

How to begin a new topic in mathematics: does it matter to students' performance in mathematics?

The authors use Canadian data from the Third International Mathematics and Science Study to examine six instructional methods that mathematics teachers use to introduce new topics in mathematics on performance of eighth-grade students in six mathematical areas (mathematics as a whole, algebra, data analysis, fraction, geometry, and measurement). Results of multilevel analysis with students nested within schools show that the instructional methods of having the teacher explain the rules and definitions and looking at the textbook while the teacher talks about it had little instructional effects on student performance in any mathematical area. In contrast, the instructional method in which teachers try to solve an example related to the new topic was effective in promoting student performance across all mathematical areas.     

Changing compatibility of cohabitation and childbearing between young British women born in 1958 and 1970

We investigate the effect of parenthood on whether non-marital unions led to marriage or parting for two cohorts of British women when they were aged between 16 and 29. We compare the effect of conceptions leading to births and the presence and characteristics of children on the odds that a cohabitation was dissolved, or that it was converted to marriage, for women born in 1958 and 1970. A multilevel, multiprocess, competing-risks model allows for multiple cohabitations per woman and endogeneity of fertility status. We find that cohabiting couples’ response to impending parenthood and the presence of children changed over time. In particular, the proportion of cohabiting couples who married before a birth decreased and, in the 1970 cohort only, the risk of dissolution declined during pregnancy. There is also evidence that the presence of a child cemented a cohabiting union for women from the 1970, but not the earlier, cohort.     

Minimal path decomposition of complete bipartite graphs

This paper deals with the subject of minimal path decomposition of complete bipartite graphs. A path decomposition of a graph is a decomposition of it into simple paths such that every edge appears in exactly one path. If the number of paths is the minimum possible, the path decomposition is called minimal. Algorithms that derive such decompositions are presented, along with their proof of correctness, for the three out of the four possible cases of a complete bipartite graph.     

Changing compatibility of cohabitation and childbearing between young British women born in 1958 and 1970

We investigate the effect of parenthood on whether non-marital unions led to marriage or parting for two cohorts of British women when they were aged between 16 and 29. We compare the effect of conceptions leading to births and the presence and characteristics of children on the odds that a cohabitation was dissolved, or that it was converted to marriage, for women born in 1958 and 1970. A multilevel, multiprocess, competing-risks model allows for multiple cohabitation per woman and endogeneity of fertility status. We find that cohabiting couples' response to impending parenthood and the presence of children changed over time. In particular, the proportion of cohabiting couples who married before a birth decreased and, in the 1970 cohort only, the risk of dissolution declined during pregnancy. There is also evidence that the presence of a child cemented a cohabiting union for women from the 1970, but not the earlier, cohort.     

Second-derivative functional regression with applications to near infra-red spectroscopy

A linear regression method to predict a scalar from a discretized smooth function is presented. The method takes into account the functional nature of the predictors and the importance of the second derivative in spectroscopic applications. This motivates a functional inner product that can be used as a roughness penalty. Using this inner product, we derive a linear prediction method that is similar to ridge regression but with different shrinkage characteristics. We describe its practical implementation and we address the problem of computing the second derivatives nonparametrically. We apply the method to a calibration example using near infra-red spectra. We conclude with a discussion comparing our approach with other regression algorithms.     

Stealing from thy Neighbour: Leveraged Recapitalizations and Wealth Redistribution

Leverage-increasing transactions such as recapitalizations and leveraged buy-outs are known to create shareholder wealth. It has been argued that the only sources of this value are efficiency improvements and tax benefits brought about by the higher debt load. This paper shows empirically that contrary to popular belief a portion of this wealth comes at the expense of current bondholders. It is estimated that between 20 per cent and SO per cent of the value created during a leveraged recapitalization can be attributed to wealth transfers from bondholders to shareholders.