| 1. |
- Ek, Simon
(author)
-
Structural Change, Match Quality, and Integration in the Labor Market
- 2023
-
Doctoral thesis (other academic/artistic)abstract
- Essay I: Are workers with poor outside opportunities less responsive and more susceptible to negative demand shifts in routine occupations? To answer this, I create and estimate an occupation specialization index (OSI) using Swedish register data and machine learning tools. It measures the expected difference in utility between a worker's occupation and his best non-routine outside option. This determines the loss he is willing to tolerate to avoid switching. Low-OSI employees disproportionately left routine work. Their future wage growth was akin to comparable workers initially in non-routine occupations. By contrast, routine specialists largely stayed put and experienced lower wage growth than generalists and non-routine specialists. Essay II (with Adrian Adermon, Georg Graetz, and Yaroslav Yakymovych): Using a new identification strategy, we jointly estimate the growth in occupational wage premia and time-varying occupation-specific life-cycle profiles for Swedish workers 1996–2013. We document a substantial increase in between-occupation wage inequality due to differential growth in premia. The association of wage premium growth and employment growth is positive, suggesting that premium growth is predominantly driven by demand side factors. Essay III (with Peter Fredriksson, Lena Hensvik, and Oskar Nordström Skans): We provide two pieces of evidence that workers' capacity to extract rents from match-specific productivity hinges on their outside options. Using a measure of match quality, derived from the relationship between workers' multidimensional skills and job-specific skill requirements, we show that: (i) wages within ongoing matches are more closely aligned with match quality following an improvement of local labor market conditions; (ii) wages of job-to-job movers are positively related to the match quality in the previous job, even when controlling for previous wage.Essay IV (with Mats Hammarstedt, and Per Skedinger): In a field experiment we study the causal effects of previous work experience and language skills when Syrian refugees in Sweden apply for low-skilled jobs. We find no evidence of sizeable effects from experience or completed language classes on the probability of receiving callback from employers. However, female applicants were more likely than males to receive a positive response. As a complement to the experiment, we interview a select number of employers.
|
|
| 2. |
- Fredriksson, Simon, 1973-
(author)
-
Proximity Ligation : Transforming protein analysis into nucleic acid detection through proximity-dependent ligation of DNA sequence tagged protein-binders
- 2002
-
Doctoral thesis (other academic/artistic)abstract
- A novel technology for protein detection, proximity ligation, has been developed along with improved methods for in situ synthesis of DNA microarrays. Proximity ligation enables a specific and quantitative transformation of proteins present in a sample into nucleic acid sequences. As pairs of so-called proximity probes bind the individual target protein molecules at distinct sites, these reagents are brought in close proximity. The probes consist of a protein specific binding part coupled to an oligonucleotide with either a free 3’- or 5’-end capable of hybridizing to a common connector oligonucleotide. When the probes are in proximity, promoted by target binding, then the DNA strands can be joined by enzymatic ligation. The nucleic acid sequence that is formed can then be amplified and quantitatively detected in a real-time monitored polymerase chain reaction. This convenient assay is simple to perform and allows highly sensitive protein detection. Parallel analysis of multiple proteins by DNA microarray technology is anticipated for proximity ligation and enabled by the information carrying ability of nucleic acids to define the individual proteins. Assays detecting cytokines using SELEX aptamers or antibodies, monoclonal and polyclonal, are presented in the thesis.Microarrays synthesized in situ using photolithographic methods generate impure products due to damaged molecules and interrupted synthesis. Through a molecular inversion mechanism presented here, these impurities may be removed. At the end of synthesis, full-length oligonucleotides receive a functional group that can then be made to react with the solid support forming an arched structure. The 3’-ends of the oligonucleotides are then cleaved, removing the impurities from the support and allowing the liberated 3’-hydroxyl to prime polymerase extension reactions from the inverted oligonucleotides. The effect of having pure oligonucleotides probes compared to ones contaminated with shorter variants was investigated in allele specific hybridization reactions. Pure probes were shown to have greater ability to discriminate between matched and singly mismatched targets at optimal hybridization temperatures.
|
|
