The dependence of marriage migrations in Japan on personal factors and ecological variables

Marriage is an important migration‐inducing life‐cycle event. This paper uses a nested logit model to explain the interprefectural migration behaviors at marriage by personal factors and prefectural attributes, based on the micro data of the 1986 national migration survey of Japan. Before marriage, each person is considered a potential migrant making a two‐level decision: (1) to stay or depart and (2) to choose a destination. The main findings are as follows.

Destination choice propensities were affected by such attributes of potential destination as income (+), employment growth (+), distance (‐), contiguity (+), and linguistic similarity (+). Non‐natives appeared to be less sensitive to the attraction of economic opportunities. Personal factors were less important than prefectural attributes in affecting destination choice propensities.

Departure propensities were affected by not only such attributes of origin prefecture as income (‐), employment growth (‐), and population density (+) but also the “inclusive variable”; (+), which reflected the attractiveness of the rest of the system. Despite being strongly emphasized in the literature, sibling status was less important than gender, nativity and education in affecting departure propensities. Personal factors were much more important than prefectural attributes in determining the departure propensities.     

The density maximization problem in graphs

We consider a framework for bi-objective network construction problems where one objective is to be maximized while the other is to be minimized. Given a host graph G=(V,E) with edge weights w _e ∈? and edge lengths ? _e ∈? for e∈E we define the density of a pattern subgraph H=(V′,E′)?G as the ratio ?(H)=∑ _e∈E′ w _e /∑ _e∈E′ ? _e . We consider the problem of computing a maximum density pattern H under various additional constraints. In doing so, we compute a single Pareto-optimal solution with the best weight per cost ratio subject to additional constraints further narrowing down feasible solutions for the underlying bi-objective network construction problem. First, we consider the problem of computing a maximum density pattern with weight at least W and length at most L in a host G. We call this problem the biconstrained density maximization problem. This problem can be interpreted in terms of maximizing the return on investment for network construction problems in the presence of a limited budget and a target profit. We consider this problem for different classes of hosts and patterns. We show that it is NP-hard, even if the host has treewidth 2 and the pattern is a path. However, it can be solved in pseudo-polynomial linear time if the host has bounded treewidth and the pattern is a graph from a given minor-closed family of graphs. Finally, we present an FPTAS for a relaxation of the density maximization problem, in which we are allowed to violate the upper bound on the length at the cost of some penalty. Second, we consider the maximum density subgraph problem under structural constraints on the vertex set that is used by the patterns. While a maximum density perfect matching can be computed efficiently in general graphs, the maximum density Steiner-subgraph problem, which requires a subset of the vertices in any feasible solution, is NP-hard and unlikely to admit a constant-factor approximation. When parameterized by the number of vertices of the pattern, this problem is W[1]-hard in general graphs. On the other hand, it is FPT on planar graphs if there is no constraint on the pattern and on general graphs if the pattern is a path.     

Bequest Expectations: Evidence from the 1989 Survey of Consumer Finances

This study uses the 1989 Survey of Consumer Finances to examine the effects of respondents' characteristics on their expectations of receiving inheritances and leaving bequests, based on altruistic bequest theory. The results of logistic regression analysis suggest that respondents' sociodemographic characteristics such as education, marital status, race, presence of living parents, and number of siblings significantly affect their anticipation of receiving an inheritance. People's expectations of leaving a bequest are found to be positively and significantly related to the value of nonliquid asset holdings, education, marital status, and positive attitude toward bequests but inversely associated with the total number of children in the household and being disabled. Those who are self-employed and middle-aged are more likely to anticipate leaving bequests.     

Private and Public Displays of Affection Among Interracial and Intra‐Racial Adolescent Couples*

Objective. This article examines variation in displays of affection between interracial and intra‐racial adolescent couples. Method. Using the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative sample of adolescents in the United States, we estimate hierarchical linear models to compare characteristics of interracial and intra‐racial relationships among white, African‐American, Hispanic, Asian American, and Native American adolescents. In our comparisons we highlight three dimensions of relationship attributes: public display, private display, and intimate physical contact. Results. Our findings suggest that interracial couples are less likely than intra‐racial couples to exhibit public and private displays of affection, but are not different from intra‐racial couples in intimate displays of affection. Conclusions. Social barriers against interracial dating still exist such that even though interracial couples are similar to intra‐racial couples in their levels of intimacy in private, they are less comfortable displaying their feelings in public.     

Asymptotics for Panel Models with Common Shocks

This article develops a novel asymptotic theory for panel models with common shocks. We assume that contemporaneous correlation can be generated by both the presence of common regressors among units and weak spatial dependence among the error terms. Several characteristics of the panel are considered: cross-sectional and time-series dimensions can either be fixed or large; factors can either be observable or unobservable; the factor model can describe either a cointegration relationship or a spurious regression, and we also consider the stationary case. We derive the rate of convergence and the limit distributions for the ordinary least square (OLS) estimates of the model parameters under all the aforementioned cases.     

DO RACE AND ETHNICITY MATTER AMONG FRIENDS?

Using the National Longitudinal Study of Adolescent Health (or Add Health), a nationally representative sample of adolescents in 1994–1995, we examine if and how friendship activities differ among interracial, interethnic, and interethnic friendships of white, black, Hispanic, and Asian youths. We find that best friends are more likely than higher-order friends to be from the same ethnic group and that best friends report more shared activities during the past week than do their higher-order friendship counterparts. Hence, we argue that shared activities is a useful indicator of friendship intimacy. In general, interracial friends report fewer shared activities than do intraracial friends, although this difference is strongest for white respondents. Moreover, we find that white, Asian, and Hispanic youths all report fewer activities with their black friends. We find little difference in friendship activities between interethnic and intraethnic friendships. Our findings suggest that, even when youths manage to break racial boundaries in friendship selection, these friendships face greater challenges than do those between individuals of the same race.     

The Enhanced Double Digest Problem for DNA Physical Mapping

The double digest problem is a common NP-hard approach to constructing physical maps of DNA sequences. This paper presents a new approach called the enhanced double digest problem. Although this new problem is also NP-hard, it can be solved in linear time in certain theoretically interesting cases.     

Test of hypotheses in panel data models when the regressor and disturbances are possibly non-stationary

This paper considers the problem of hypothesis testing in a simple panel data regression model with random individual effects and serially correlated disturbances. Following Baltagi et al. (Econom. J. 11:554–572, 2008), we allow for the possibility of non-stationarity in the regressor and/or the disturbance term. While Baltagi et al. (Econom. J. 11:554–572, 2008) focus on the asymptotic properties and distributions of the standard panel data estimators, this paper focuses on testing of hypotheses in this setting. One important finding is that unlike the time-series case, one does not necessarily need to rely on the “super-efficient” type AR estimator by Perron and Yabu (J. Econom. 151:56–69, 2009) to make an inference in the panel data. In fact, we show that the simple t-ratio always converges to the standard normal distribution, regardless of whether the disturbances and/or the regressor are stationary.     

Estimation and identification of change points in panel models with nonstationary or stationary regressors and error term

This article studies the estimation of change point in panel models. We extend Bai (2010 Bai, J. (2010). Common breaks in means and variances for panel data. Journal of Econometrics 157:78–92.[Crossref], [Web of Science ®] , [Google Scholar]) and Feng et al. (2009 Feng, Q., Kao, C., Lazarová, S. (2009). Estimation and Identification of Change Points in Panel Models, Working paper, Syracuse University. [Google Scholar]) to the case of stationary or nonstationary regressors and error term, and whether the change point is present or not. We prove consistency and derive the asymptotic distributions of the Ordinary Least Squares (OLS) and First Difference (FD) estimators. We find that the FD estimator is robust for all cases considered.     

A manually-checkable proof for the NP-hardness of 11-color pattern self-assembly tileset synthesis

Patterned self-assembly tile set synthesis (pats) aims at minimizing the number of distinct DNA tile types used to self-assemble a given rectangular color pattern. For an integer k, k-pats is the subproblem of pats that restricts input patterns to those with at most k colors. We give an efficient Open image in new window verifier, and based on that, we establish a manually-checkable proof for the NP-hardness of 11-pats; the best previous manually-checkable proof is for 29-pats.