Methods of trench excavation

Thesis (B.S.)--University of Illinois, 1912.Typescript

The gendered impacts of delayed parenthood on educational and labor market outcomes : a dynamic analysis of population-level effects over young adulthood

Later parenthood is often beneficial for women, but less is known about its impact on men. As first births continue to occur later in life, it is important to understand whether this delay influences the educational and labor market outcomes of women and men differently, and how it changes the socioeconomic characteristics of children’s parents at birth. However, education, employment, and fertility are linked, implying that complex models are required in order to analyze the time-varying impacts of delayed parenthood. We use dynamic longitudinal models and Finnish data to analyze how, and through which socioeconomic mechanisms, a material delay in parenthood is likely to influence educational and labor market outcomes over young adulthood. A three-year delay in young-adult parenthood for all women increases educational enrollment in their early 20s, employment in their late 20s, and partly due to higher education income in their 30s. The impact of the same delay for men is more modest, and almost negligible for their employment, suggesting that later parenthood exacerbates the educational advantage of women and attenuates the income advantage of men. However, it strengthens the socioeconomic standing of both men and women when they become parents, essentially due to the accumulation of effects

The gendered impacts of delayed parenthood on educational and labor market outcomes : a dynamic analysis of population-level effects over young adulthood

Later parenthood is often beneficial for women, but less is known about its impact on men. As first births continue to occur later in life, it is important to understand whether this delay influences the educational and labor market outcomes of women and men differently, and how it changes the socioeconomic characteristics of children’s parents at birth. However, education, employment, and fertility are linked, implying that complex models are required in order to analyze the time-varying impacts of delayed parenthood. We use dynamic longitudinal models and Finnish data to analyze how, and through which socioeconomic mechanisms, a material delay in parenthood is likely to influence educational and labor market outcomes over young adulthood. A three-year delay in young-adult parenthood for all women increases educational enrollment in their early 20s, employment in their late 20s, and partly due to higher education income in their 30s. The impact of the same delay for men is more modest, and almost negligible for their employment, suggesting that later parenthood exacerbates the educational advantage of women and attenuates the income advantage of men. However, it strengthens the socioeconomic standing of both men and women when they become parents, essentially due to the accumulation of effects

The gendered impacts of delayed parenthood: A dynamic analysis of young adulthood

Young adulthood is a dynamic and demographically dense stage in the life course. This poses a challenge for research on the socioeconomic consequences of parenthood timing, which most often focuses on women. We chart the dynamics of delayed parenthood and its implications for educational and labor market trajectories for young adult women and men using a novel longitudinal analysis approach, the parametric g-formula. This method allows the estimation of both population-averaged effects (among all women and men) and average treatment effects (among mothers and fathers). Based on high-quality data from Finnish registers, we find that later parenthood exacerbates the educational advantage of women in comparison to men and attenuates the income advantage of men in comparison to women across young adult ages. Gender differences in the consequences of delayed parenthood on labor market trajectories are largely not explained by changes in educational trajectories. Moreover, at the time of entering parenthood, delayed parenthood improves the incomes of fathers more than those of mothers, thereby exacerbating existing gender differences. The results provide population-level evidence on how the delay of parenthood has contributed to the strengthening of women’s educational position relative to that of men. Further, the findings on greater increases in fathers’ than mothers’ incomes at the time of entering parenthood, as followed by postponement, may help explain why progress in achieving gender equality in the division of paid and unpaid work in families has been slow.Peer reviewe

Modelling the socio-economic determinants of fertility: a mediation analysis using the parametric g-formula

Theories predict that the timing of childbearing and number of children born are determined by multiple socio-economic factors. Despite this, many methods cannot investigate the interrelationships between these determinants, including the direct and indirect influence that they have on fertility over the life course. Here we use the parametric g-formula to examine the interdependent influences of time-varying socio-economic processes, education, employment status and partnership status?on fertility. To demonstrate this approach, we study a cohort of women who were born in the UK in 1970. Our results show that socio-economic processes play an important role in determining fertility, not only directly but also indirectly. We show that increasing attendance in higher education has a largely direct effect on early childbearing up to age 25 years, resulting in a substantial increase in childlessness. However, childbearing at later ages is dominated by an indirect effect of education on fertility, via partnership status and employment status, that is twice as large as the direct effect. We also use the g-formula to examine bias due to unobserved heterogeneity, and we demonstrate that our results appear to be robust. We conclude that the method provides a valuable tool for mediation analysis in studies of interdependent life course processes

Block Spin Effective Action for 4d SU(2) Finite Temperature Lattice Gauge Theory

The Svetitsky-Yaffe conjecture for finite temperature 4d SU(2) lattice gauge theory is confirmed by observing matching of block spin effective actions of the gauge model with those of the 3d Ising model. The effective action for the gauge model is defined by blocking the signs of the Polyakov loops with the majority rule. To compute it numerically, we apply a variant of the IMCRG method of Gupta and Cordery.Comment: LaTeX2e, 22 pages, 8 Figure

Childhood IQ and marriage by mid-life: the Scottish Mental Survey 1932 and the Midspan Studies

The study examined the influence of IQ at age 11 years on marital status by mid-adulthood. The combined databases of the Scottish Mental Survey 1932 and the Midspan studies provided data from 883 subjects. With regard to IQ at age 11, there was an interaction between sex and marital status by mid-adulthood (p = 0.0001). Women who had ever-married achieved mean lower childhood IQ scores than women who had never-married (p < 0.001). Conversely, there was a trend for men who had ever-married to achieve higher childhood IQ scores than men who had never-married (p = 0.07). In men, the odds ratio of ever marrying was 1.35 (95% CI 0.98–1.86&#59; p = 0.07) for each standard deviation increase in childhood IQ. Among women, the odds ratio of ever marrying by mid-life was 0.42 (95% CI 0.27–0.64; p = 0.0001) for each standard deviation increase in childhood IQ. Mid-life social class had a similar association with marriage, with women in more professional jobs and men in more manual jobs being less likely to have ever-married by mid-life. Adjustment for the effects of mid-life social class and height on the association between childhood IQ and later marriage, and vice versa, attenuated the effects somewhat, but suggested that IQ, height and social class acted partly independently

Modeling the Emergence of Whisker Direction Maps in Rat Barrel Cortex

Based on measuring responses to rat whiskers as they are mechanically stimulated, one recent study suggests that barrel-related areas in layer 2/3 rat primary somatosensory cortex (S1) contain a pinwheel map of whisker motion directions. Because this map is reminiscent of topographic organization for visual direction in primary visual cortex (V1) of higher mammals, we asked whether the S1 pinwheels could be explained by an input-driven developmental process as is often suggested for V1. We developed a computational model to capture how whisker stimuli are conveyed to supragranular S1, and simulate lateral cortical interactions using an established self-organizing algorithm. Inputs to the model each represent the deflection of a subset of 25 whiskers as they are contacted by a moving stimulus object. The subset of deflected whiskers corresponds with the shape of the stimulus, and the deflection direction corresponds with the movement direction of the stimulus. If these two features of the inputs are correlated during the training of the model, a somatotopically aligned map of direction emerges for each whisker in S1. Predictions of the model that are immediately testable include (1) that somatotopic pinwheel maps of whisker direction exist in adult layer 2/3 barrel cortex for every large whisker on the rat's face, even peripheral whiskers; and (2) in the adult, neurons with similar directional tuning are interconnected by a network of horizontal connections, spanning distances of many whisker representations. We also propose specific experiments for testing the predictions of the model by manipulating patterns of whisker inputs experienced during early development. The results suggest that similar intracortical mechanisms guide the development of primate V1 and rat S1

Renormalization Group and Universality

It is argued that universality is severely limited for models with multiple fixed points. As a demonstration the renormalization group equations are presented for the potential and the wave function renormalization constants in the $O(N)$ scalar field theory. Our equations are superior compared with the usual approach which retains only the contributions that are non-vanishing in the ultraviolet regime. We find an indication for the existence of relevant operators at the infrared fixed point, contrary to common expectations. This result makes the sufficiency of using only renormalizable coupling constants in parametrizing the long distance phenomena questionable.Comment: 32pp in plain tex; revised version to appear in PR

Quantum and Thermal Fluctuations in Field Theory

Blocking transformation is performed in quantum field theory at finite temperature. It is found that the manner temperature deforms the renormalized trajectories can be used to understand better the role played by the quantum fluctuations. In particular, it is conjectured that domain formation and mass parameter generation can be observed in theories without spontaneous symmetry breaking.Comment: 27pp+7 figures, MIT-CTP-214