| 1. |
- Johansson, Elly-Ann, 1978-
(författare)
-
Essays on schooling, gender, and parental leave
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis consists of four self-contained essays. Essay 1: Mixed-aged classes (MA-classes) are a common phenomenon around the world. In Sweden, these types of classes increased rapidly during the 1980:s and 1990:s, despite the fact that existing empirical support for MA-classes is weak. In this paper, we estimate the effect of attending an MA-class during grades 4-6 on students’ cognitive skills. Using a unique survey with information on students, parents and teachers, we are able to control for many factors that could otherwise bias the results. We find a negative effect on short-run cognitive skills, as measured by grade 6 cognitive tests, and this effect is robust to a rigorous sensitivity analysis. Essay 2: We examine whether the impact of pre-school interventions on cognitive skills differs by immigrant background. The analysis is based on Swedish data containing information on childcare attendance, rich family background information, the performance on cognitive tests at age 13, and long-run educational attainment for cohorts born between 1967 and 1982. We find that childcare attendance reduces the gap in language skills between children from immigrant backgrounds relative to native-born children. We find no differential effects on inductive skills, however. Nor does childcare appear to affect the distribution of long-run educational attainment. Essay 3: This paper estimates the effect of child gender on mothers’ and fathers’ parental leave. The focus on Sweden, a highly gender equal society, yields additional knowledge on the prevalence of gender biases in industrialized countries. The results show that a first born son increases fathers’ parental leave with 0.6 days (1.5 percent) and decreases mothers’ leave by a similar amount, leaving the total leave unchanged. Both the sign and size of this effect is in line with previous research. However, there are interesting differences between groups that departs from previous studies. Non-traditional families, with high maternal relative earnings and/or educational levels, show even larger gender biases, indicating that it may be mothers, rather than fathers, that are the driving force behind this child gender bias. Essay 4: This paper investigates the effect of parental leave – both own and spousal – on subsequent earnings using different sources of variation. Using fixed-effects models, and in line with previous results, parental leave is found to decrease each parent’s future earnings. Also spousal leave is important, but only for mothers. In fact, each month the father stays on parental leave has a larger positive effect on maternal earnings than a similar reduction in the mother’s own leave. Using two reforms of the parental leave system as exogenous sources of variation yields only imprecisely estimated effects, even though the reforms had a strong effect on parental leave usage. However, the point estimates tentatively suggest effects in the same range or larger than the fixed-effects model found.
|
|
| 2. |
- Lagerström, Jonas, 1974-
(författare)
-
Discrimination, Sickness Absence, and Labor Market Policy
- 2006
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation consists of an introduction and four self-contained essays:Essay 1 (with Stefan Eriksson) investigates empirically whether being unemployed per se reduces the probability of getting contacted by a firm. Individuals registered at the Swedish employment offices post their qualifications in a database available to employers over the Internet. Since we have access to exactly the same information as the firms, we can minimize the problems associated with unobserved heterogeneity. Our results show that an unemployed applicant faces a lower contact probability, and receives fewer contacts, than an otherwise identical employed applicant, thus supporting the notion that firms view employment status as a signal for productivity.Essay 2 evaluates an experiment where employees at randomly chosen establishments received half a day off if they completed a full calendar month without any sick-leave. Using individual panel data, the absence rates of these individuals are compared to the absence rates of individuals at establishments with no such program before, during and after the treatment periods. Overall, the bonus caused a sharp reduction in absenteeism, especially for women, highly educated individuals and part-time workers. Essay 3 (with Per-Anders Edin) provides evidence on discrimination in the hiring process. We use Internet data generated from a “policy experiment”, in which individuals can choose not to reveal their name and gender to potential employers. By comparing the “contact rate” of censored and non-censored women and minorities, we find that women have a 20 percent lower chance than men of getting contacted by employers and that this differential is fully explained by discrimination. Our results concerning ethnic discrimination are less conclusive, probably due to measurement errors.Essay 4 examines if and how the personnel at the Swedish Employment Office matter. The analysis shows that caseworkers explain a substantial part of future outcomes in terms of employment status and earnings, but have no significant effect on wages. Caseworkers that send their clients to classroom training or on-the-job training are less successful than caseworkers that provide basic job-search assistance. If caseworkers’ preferences in previous years towards treatments are uncorrelated with unobserved present working strategies, these estimates correspond to causal treatment effects.
|
|
| 3. |
- Magnusson, Lena, 1961-
(författare)
-
On the Nucleation and Inoculation of Metals
- 2006
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Latent heat during recalesence and nucleation and post-recalesence temperature was analysed for refractory metals. An effect on latent heat was found by alloying the pure elements with other refractories. Latent heat was found to be 15-65% of tabulated values. Interface energy was evaluated from undercooling experiments. It was found that the dimensionless numbers β (σLs/ σLv) and α can be used to classify elements into distinctive groups and crystallographic structure. The phase diagrams for Al-Ti, Al-Ti-B and Al-Ti-C as well as inoculation were analysed. It was found that Al nucleates on Al3Ti which nucleates on TiB2. TiC was found to decompose into Al4C3 and Al3Ti. The inoculation of nodular cast iron with Mg, Ce; Ca and the formation of sulphides and oxides was analysed. The formation of new inclusions during the solidification as well as the formation of graphite is discussed.
|
|
| 4. |
- Söderström, Martin, 1975-
(författare)
-
Evaluating Institutional Changes in Education and Wage Policy
- 2006
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis consists of four self-contained essays. Essay I (written with Roope Uusitalo) studies the effects of school choice on segregation. We analyse a reform in Stockholm that changed the admission system of public upper secondary schools. Before 2000, students were assigned to their nearest school, but from the fall of 2000, students can apply to any school, and admission is based on grades only. The distribution of students over schools changed dramatically as a response to extending school choice. As expected, segregation by ability increased. However, segregation by family background, as well as, segregation between immigrants and natives also increased significantly. Furthermore, the increase in segregation between immigrants and natives is not explained by differences in prior achievement.Essay II studies the effects of school choice on student achievement by analysing the Stockholm admission reform. Since all schools became open for application from anyone, and funding follows the students, the reform imposed strong incentives for school competition. It is shown that the reform has contributed to increase the between school variance in student outcomes. More importantly, the results indicate that students in Stockholm perform no better with increased choice availability. Essay III evaluates the introduction of individual wage bargaining for Swedish teachers. A centralized bargaining structure with wage scales was in 1996 replaced by a decentralized one, where teachers now negotiate their own wages. This paper investigates whether this system was a binding constraint, by studying the earnings structure of teachers during the 1990s. The results indicate reform effects, most pronounced for compulsory school teachers; both the age profile of earnings and earnings dispersion shifted. Furthermore, there are no indications that the returns to education and certification increase after the reform.Essay IV (written with Peter Fredriksson) examines the relationship between unemployment benefits and unemployment using Swedish regional data. To estimate the effect of an increase in unemployment insurance (UI) on unemployment we exploit the fact the generosity of UI varies regionally because there is a ceiling on benefits. The actual generosity of UI varies within region over time due to, e.g., differences in expected regional wage growth and variations in the benefit ceiling. We find that the actual generosity of UI does matter for regional unemployment. Increases in the actual replacement rate contribute to higher unemployment. We also show that removing the wage cap in UI benefit receipt would reduce the dispersion of regional unemployment.
|
|
