Ability Bias, Skewness and the College Wage Premium

Changes in educational participation rates across cohorts are likely to imply changes in the ability-education relationship and thereby to impact on estimated returns to education. We show that skewness in the underlying ability distribution is a key determinant of the impact of graduate expansion on the college wage premium. Calibrating the model against the increased proportion of university students in Britain, we find that changes in the average ability gap between university students and others are likely to have mitigated demand-side forces.Ability Bias ; College Wage Premium ; Graduate Returns ; Cohort Effects

Am I missing something? The effects of absence from class on student performance

We exploit a rich administrative panel data-set for cohorts of Economics students at a UK university in order to identify causal effects of class absence on student performance. We exploit the panel properties of the data to control for unobserved heterogeneity across students and hence for endogeneity between class absence and academic performance of students stemming from the likely influence of effort and ability on both absence and performance. Our estimations also exploit features of the data such as the random assignment of students to classes and information on the timetable of classes, which provides potential instruments in our identification strategy. Among other results we find, from a quantile regression specification, that there is a causal effect of absence on performance for students : missing class leads to poorer performance. There is evidence that this is particularly true for better-performing students, consistent with our hypothesis that effects of absence on performance are likely to vary with factors such as student ability.Randomised experiments ; quantile regression ; selection correction ; panel data ; education ; student performance ; class absence

Educational Returns, ability composition and cohort effects : theory and evidence for cohorts of early-career UK graduates

An increase over time in the proportion of young people obtaining a degree is likely to impact on the relative ability compositions (i) of graduates and non-graduates and (ii) across graduates with different classes of degree award. In a signalling framework, we examine the implications of this on biases across cohorts in estimates of educational returns. In an empirical analysis, we exploit administrative data on whole populations of UK university students for ten graduate cohorts to investigate the extent to which early labour market outcomes vary with class of degree awarded. Consistent with our theoretical model, we find that returns by degree class increased across cohorts during a period of substantial graduate expansion. We also corroborate the empirical findings with evidence from complementary data on graduate sample surveys.Educational Returns ; College Wage Premium ; Degree Class ; Ability Bias ; Statistical Discrimination

Doctor who? Who gets admission offers in UK medical schools

In the context of the UK Government’s ambitious programme of medical school expansion, it is important to have an understanding of how the medical school admissions process works, and with what effects. The issue is also relevant for the Schwartz Review (2004) into higher education admissions. Using individual-level data for two entire cohorts of medical student applicants in UK universities and exploiting the panel structure of the applicant-medical school information, we estimate models to analyse the probability that an individual student receives an offer of a place. We find that prior qualifications, school type, gender, age, social class and ethnic background are major influences on whether a student receives an offer from a medical school. We also find that the probability of receiving an offer from a particular medical school is influenced by the identity of other medical schools applied to. Finally, we find evidence that certain groups of applicants are particularly disadvantaged the later they apply within the application process

Tax Evasion, Social Customs and Optimal Auditing

Abstract: The optimal audit policy is analysed for an independent revenue service when a social custom exists that rewards honest tax-paying. The implication of the existence of the social custom is that in equilibrium the income level of a taxpayer cannot always be inferred exactly from their report. The structure of the optimal audit policy is determined both for a fixed (report-invariant) audit probability and for when the audit probability is a function of the income report. For the constant probability of audit it is shown that an interior solution exists to the decision problem of the revenue service and comparative statics results are given. When the audit probability can vary, the audit function is proved to be a decreasing function of the income report which reaches zero at the highest income report of a tax evader. Increases in the fine for evading and in the tax rate raise the optimal audit probability

A hazard model of the probability of medical school dropout in the United Kingdom

From individual level longitudinal data for two entire cohorts of medical students in UK universities, we use multilevel models to analyse the probability that an individual student will drop out of medical school. We find that academic preparedness—both in terms of previous subjects studied and levels of attainment therein—is the major influence on withdrawal by medical students. Additionally, males and more mature students are more likely to withdraw than females or younger students respectively. We find evidence that the factors influencing the decision to transfer course differ from those affecting the decision to drop out for other reasons

Challenges in multidisciplinary cancer care among general surgeons in Canada

<p>Abstract</p> <p>Background</p> <p>While many factors can influence the way that cancer care is delivered, including the way that evidence is packaged and disseminated, little research has evaluated how health care professionals who manage cancer patients seek and use this information to identify whether and how this could be supported. Through interviews we identified that general surgeons experience challenges in coordinating care for complex cancer patients whose management is not easily addressed by guidelines, and conducted a population-based survey of general surgeon information needs and information seeking practices to extend these findings.</p> <p>Methods</p> <p>General surgeons with privileges at acute care hospitals in Ontario, Canada were mailed a questionnaire to solicit information needs (task, importance), information seeking (source, frequency of and reasons for use), key challenges and suggested solutions. Non-responders received up to three reminder packages. Significant differences among sub-groups (age, setting) were examined statistically (Kruskal Wallis, Mann Whitney, Chi Square). Standard qualitative methods were used to thematically analyze open-ended responses.</p> <p>Results</p> <p>The response rate was 44.2% (170/385) representing all 14 health regions. System resource constraints (60.4%), comorbidities (56.4%) and physiologic factors (51.8%) were top-ranked issues creating information needs. Local surgical colleagues (84.6%), other local colleagues (82.2%) and the Internet (81.1%) were top-ranked sources of information, primarily due to familiarity and speed of access. No resources were considered to be highly applicable to patient care. Challenges were related to limitations in diagnostics and staging, operative resources, and systems to support multidisciplinary care, together accounting for 76.0% of all reported issues. Findings did not differ significantly by surgeon age or setting of care.</p> <p>Conclusion</p> <p>General surgeons appear to use a wide range of information resources but they may not address the complex needs of many cancer patients. Decision-making is challenged by informational and logistical issues related to the coordination of multidisciplinary care. This suggests that limitations in system capacity may, in part, contribute to variable guideline compliance. Further research is required to evaluate the appropriateness of information seeking, and both concurrent and consecutive mechanisms by which to achieve multidisciplinary care.</p

Multimarket Linkages, Buyer Power, and the Productivity Puzzle

This paper examines the relationship between firms' productivity improvement and the volume of exports, and shows that it can be sometimes negative. Specifically, we simultaneously take into account intermediate retailers (i.e., vertically) and multimarket linkages (i.e., horizontally). We find that an improvement of the manufacturing productivity affects the bargained wholesale prices in opposite directions in asymmetric markets, causing retailers to make corresponding changes that look surprising. This result can explain for the empirical productivity puzzle found in Ghemawat et al. (2010). Related to this issue is the relationship between buyer power (caused by a retail merger) and profitability. Contrary to the existing literature, in an extended setup, we find that the merger between the downstream duopolists does not improve their profits if their bargaining power is strong vs. upstream suppliers

Posttraumatic Stress Disorder Symptom Network Analysis in U.S. Military Veterans: Examining the Impact of Combat Exposure

Recent work inspired by graph theory has begun to conceptualize mental disorders as networks of interacting symptoms. Posttraumatic stress disorder (PTSD) symptom networks have been investigated in clinical samples meeting full diagnostic criteria, including military veterans, natural disaster survivors, civilian survivors of war, and child sexual abuse survivors. Despite reliable associations across reported networks, more work is needed to compare central symptoms across trauma types. Additionally, individuals without a diagnosis who still experience symptoms, also referred to as subthreshold cases, have not been explored with network analysis in veterans. A sample of 1,050 Iraq/Afghanistan-era U.S. military veterans (851 males, mean age = 36.3, SD = 9.53) meeting current full-criteria PTSD (n = 912) and subthreshold PTSD (n = 138) were assessed with the Structured Clinical Interview for DSM-IV Disorders (SCID). Combat Exposure Scale (CES) scores were used to group the sample meeting full-criteria into high (n = 639) and low (n = 273) combat exposure subgroups. Networks were estimated using regularized partial correlation models in the R-package qgraph, and robustness tests were performed with bootnet. Frequently co-occurring symptom pairs (strong network connections) emerged between two avoidance symptoms, hypervigilance and startle response, loss of interest and detachment, as well as, detachment and restricted affect. These associations replicate findings reported across PTSD trauma types. A symptom network analysis of PTSD in a veteran population found significantly greater overall connectivity in the full-criteria PTSD group as compared to the subthreshold PTSD group. Additionally, novel findings indicate that the association between intrusive thoughts and irritability is a feature of the symptom network of veterans with high levels of combat exposure. Mean node predictability is high for PTSD symptom networks, averaging 51.5% shared variance. With the tools described here and by others, researchers can help refine diagnostic criteria for PTSD, develop more accurate measures for assessing PTSD, and eventually inform therapies that target symptoms with strong network connections to interrupt interconnected symptom complexes and promote functional recovery

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead