Thesis advisor: Arthur Lewbel / This dissertation consists of three related chapters. A unifying feature throughout all is a focus on the issues in the economics of crime, specifically in how different factors affect different types of index crimes. The first chapter, a collaboration with Abby Hong, examines the role of the stand-your-ground law in driving first-degree and second-degree murder rates. The second chapter, a collaboration with Benjamin Ferri, examines how the two ends of the income distribution impact emotional gain crime and financial gain crime. Both chapters one and two examine how different variables affect crime, and both have a theoretical part and an empirical part. The third chapter looks into measurement issues in crime. Specifically, it considers the impact of a change in data collection methods on the Uniform Crime Report (UCR). The first chapter, “Self-defense Regulations and Crime: Evidence from the Stand Your Ground Law,” provides a theoretical model of crime escalation when governments relax self-defense regulations. We then test the model with an empirical analysis of the “stand-your-ground” (SYG) laws’ impact on planned and unplanned murders. The game theoretical model shows that relaxing self-defense regulations can increase the arming of crime victims. It also increases the arming of offenders in crimes that lead to unplanned murders. If planned murder offenders are over-confident, then their level of arms increases as well. We then use a difference-in-differences (DiD) model to test these implications. We find that consistent with the model, SYG laws in the US increase the planned murder rate by 7.6% and the unplanned murder rate by 10.4%, on average. Also, the effect size increases over time, highlighting the persistence of the impact. The paper illustrates how interactions between victims and offenders result in unintended consequences of self-defense regulations. It also encourages policymakers to take into account criminal behavior when making policy decisions. The second chapter, “The Distinct Roles of Poverty and Higher Earnings in Motivating Crime,” develops a new model that articulates how Poverty (the lower tail of the earnings distribution) and Earnings (the upper tail) enter into equilibrium crime rates. In our model, individuals in Poverty have less to lose in the context of criminal punishment, so are less averse to committing crimes in general. The presence of high Earnings (therefore things worth stealing) heightens the expected gain to offenders per crime - but specifically in terms of financial gain, not emotional gain. We estimate our model on a comprehensive panel of U.S. Commuting Zones (1980-2016), deploying novel Shift-Share instruments to correct for reverse causality (of crime on the earnings distribution). Corroborating our hypothesis, we find that high Earnings plays a much larger role in driving crimes that yield financial gain to the offender (various forms of theft) than it does for crimes of emotional gain; while Poverty is a driving force equally across both types of crime. In each case, not accounting for reverse causality would underestimate both effects, often by more than double. The third and final chapter, “Crime Reporting Standards and Reported Crime,” This paper explores data discrepancies in the Uniform Crime Report (UCR) before and after the adoption and conversion of the National Incident-Based Reporting System (NIBRS). The FBI starts publishing the UCR in 1930 to understand crime trends in the United States. The UCR is published under the Summary Reporting System (SRS) until the 1990s, when the NIBRS is developed to collect more detailed data. The NIBRS is then converted to “synthetic SRS” and concatenated to historical SRS data when it enters the UCR. It uses a staggered event study design based on the year in which the agency switches from the SRS to the NIBRS. I find two factors that contribute to a large and statistically significant increase in reported crime for agencies that adopt the NIBRS compared with agencies that have not: the data conversion process and a change in reporting practices. When I convert the NIBRS to synthetic SRS based on published criteria, I observe a smaller and statistically insignificant increase in assault cases. However, this alternative conversion process does not improve the difference-in-differences (DiD) effects for total crime, murder, robbery, burglary, and theft, highlighting the fact that data from the NIBRS is more complete and more timely. / Thesis (PhD) — Boston College, 2023. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

A study of the frequency response and gain of Solid-state the Impact-ionization Multiplier (SIM). The SIM generates current gain via impact ionization also known as avalanche gain. The SIM provides low noise amplification from an arbitrary current source. In the case of this study, current sources consisted of photodiodes optimized for a particular wavelength of light. The SIM is fabricated from silicon and enjoys the low noise, low carrier transit time advantages of conventional silicon impact ionization devices while amplifying current from a photodiode of a different material. This is advantageous because ideal detection and multiplication regions cannot always be grown on the same wafer. Furthermore a photodiode fitted to a SIM allows absorption and multiplication regions to be independently optimized. The SIM exhibits a current dependant input resistance. This resistance in combination with field effects from the SIM collector is the limiting factor in the frequency response of the SIM. Frequency response is improved to the extent that this floating voltage at the input can be minimized. Higher AC gains are realized in the device with the incorporation of 3-dimensional geometries. These improvements allow for improved device breakdown and reduced space-charge resistance at high input currents. Frequency response can also be improved by increasing the current flowing into the SIM, this current is most often in the form of DC current such that it can be filtered off at a the output and not interfere with the input signal.

No description available.

The increasing prevalence of overweight and obesity suggests that current policies and interventions have been inadequate to counteract the driving forces. Young adults attending college gain weight at a faster rate than the general population, without evidence of compensatory weight loss. Therefore, college may be an important stage for the primary prevention of obesity. We sought to identify weight gain mediators in college underclassmen using the social cognitive model for health behavior change. Eligible students living on-campus to underwent assessments of height, weight, waist circumference, blood pressure, body composition, cardiorespiratory fitness, habitual physical activity and dietary intake, and psychosocial determinants of health behavior change. We conducted elicitation interviews and focus group discussions to identify themes related to the diet and physical activity habits, attitudes, social norms, and experiences of the target population. Results found that students were generally physically fit and enjoyed a variety of physical activities, yet spent considerable amounts of time in sedentary activity and had difficulty exercising regularly. Healthy eating perceptions were instilled by parents; however, families are much less influential in college, and students almost always eat with friends. Healthy eating and exercise habits were secondary to several other responsibilities. Skills in planning, goal setting, and self-monitoring are necessary to overcome the social and environmental forces contributing to weight gain. These results will be used to develop a social cognitive theory-based intervention to improve health behaviors, and consequently prevent weight gain in young adults attending college. / Master of Science

Fiber Raman amplification using the transmission line is a promising technology to increase the repeater distance as well as the capacity of the communication systems. Because of the growing importance of fiber Raman amplification, it is desired to predict the magnitude and shape of the Raman gain spectrum from the doping level and refractive index profiles of different fiber designs. This thesis develops a method to predict the Raman gain coefficients and spectra for a pure silica core fiber and two different types of GeO2-doped silica fibers given their index profiles. An essential feature of the model is the inclusion of the variation in Raman gain coefficient over the mode field due to the variation in the Ge concentration across the fiber core. The calculated Raman gain coefficients were compared with measurements of the peak Raman gain on a step-index GeO2-doped fiber and with published measurements from various sources. Agreement between the calculated and measured peak gain for the step-index fiber was excellent. There was qualitative agreement with published measurements but there were significant differences between the calculated and published gain coefficients, which are not understood. Part of the work sought a way of predicting Raman gain coefficients from a standard gain curve given only the fiber type and the effective area. This approach appears promising for moderately-doped fibers with the proper choice of effective area. / Master of Science

No / Background Anecdotally, it has long been felt by academic staff that students on the Bradford 5-year sandwich degree programme (intercalated pre-registration training) performed differently on return to university from those on the continuous 4-year programme. Direct comparisons between cohorts have been difficult to undertake as the two groups were taught separately in their final stage. In 2016-17, a cohort of returning sandwich students was taught alongside a comparable group of continuous students in a final stage module. This study compares the results from these two student cohorts. Method The Pharmacy Special Studies module offered a very broad range of opportunities across laboratory research, systematic and scoping review, product development and care-orientated topics including audit, and analysis of clinical cases, organised in 9 separate “strands.” Students from the sandwich (n=99) and continuous (n=89) courses were offered the same selection of learning experiences. Assessment was by oral presentation and discussion (slides or poster) and written report. The Level 7 marking schemes used were designed so that the highest marks were only available to reward student demonstration of the higher-level critical, analytical and interpretative skills. Results Student performance across all 9 strands of the module was comparable. When module results were split according to cohort, a strong divergence was observed. Sandwich student results displayed an approximately bell-shaped distribution with a mean mark 73.2% (SD 8.1). In contrast, the continuous student results had a lower mean 67.3% (SD 8.5, p<10-5); moreover, the distribution of these marks was distorted with a ‘cliff edge’ in the low 70s and a long tail. Conclusion This analysis shows that students who had completed 6 months pre-registration training achieved, on average, higher grades. Moreover, they demonstrated improved higher-level skills of interpretation and critical analysis compared with the continuous group. Although this is a one-year “snapshot” observation it appears to show that following 6 months preregistration training, students are better able to critically evaluate and interpret data and draw evidence-based conclusions. Such a result could provide evidence for the benefits of intercalated placements and indicate the optimal location of professional training within the academic course. Any impact on pre-registration training itself remains to be determined. / Abstract, presented at the Pharmacy Education Conference 2017, Manchester, United Kingdom.

Ce manuscrit porte sur la synthèse d'observateurs grand gain pour des systèmes non linéaires à sorties échantillonnées et retardées. Trois contributions sont proposées à la lecture de ce manuscrit. La première contribution, pour une classe de systèmes Multi-entrées / Multi-sorties uniformément observables et dont les sorties sont regroupées en un seul bloc, met en jeu le problème du processus d'acquisition des mesures de sorties (continues, échantillonnées, retardées ou non) et propose un cadre commun pour l'ensemble des cas possibles. La deuxième contribution propose un observateur grand gain filtré sur cette même classe de systèmes dans l'optique de réduire la sensibilité au bruit de mesure, dans le cas où la sortie est continue puis dans le cas où cette dernière est échantillonnée. La dernière contribution vise à étendre la synthèse grand gain standard pour une large classe de systèmes Multi-entrées / Multi-sorties uniformément observables dont les mesures des sorties sont continues. Pour chacune de ces contributions, il a été montré que l'erreur d'observation de chacun des observateurs proposés converge exponentiellement vers zéro en l'absence d'incertitudes sur le système. Toutes ces contributions ont été illustrées par différents exemples issus de plusieurs domaines d'étude. / This manuscript deals with the synthesis of high gain observers for nonlinear systems with sampled and delayed outputs. Three contributions are proposed for consideration in this manuscript. The first contribution, for a class of Multi-input / Multi-output systems whose outputs are grouped into a single block, involves the problem of the acquisition process of output measurements (continuous, sampled, delayed or not) and proposes a common framework for all possible cases. The second contribution proposes a filtered high gain observer on this same class of systems in order to reduce the sensitivity to measurement noise, in the case where the output is continuous and then in the case where the latter is sampled. The last contribution aims to extend the standard high gain synthesis for a large class of uniformly observable Multi-input / Multi-output systems with continuous output measurements. For each of these contributions, it has been shown that the observation error of each of the proposed observers converges exponentially towards zero in the absence of uncertainties in the system. All these contributions have been illustrated through several examples from different fields of study.

Master of Science / Department of Kinesiology / Thomas J. Barstow / Purpose: Oxygen uptake (VO2) has been shown to be controlled by a nonlinear system, yet the VO2 response to ramp style exercise appears linear. We tested the hypothesis that an integrative model incorporating nonlinear parameter values could accurately estimate actual VO2 responses to ramp style exercise. Methods: Six healthy, men completed three bouts of varying ramp rate exercise (slow ramp (SR): 15 W/min, regular ramp (RR) 30 W/min, fast ramp (FR) 60W/min) and four bouts of extended-step incremental exercise, where each step lasted 5-15 min or until volitional fatigue on a cycle ergometer on separate days. The step-responses were then fit with a simple monoexponential starting at time zero (MONO) or allowing a time delay and using only the first 5 min of data (5TD). The resulting VO2 parameters from the step protocol were incorporated into an integrative model for the estimation of the VO2 response to each of the rates of ramp incremental exercise. The parameters from the actual and model ramp protocols were compared with 2 way repeated-measures ANOVAs. Results: Both Gain (G) and Mean Response Time (MRT) (or time constant) values increased significantly across work rate transitions (mean±SD; Gain:10.0±0.9, 11.6±1.1, 13.1±1.3, 17.6±3.3 ml O2/min/W; MRT:39.4±7.7, 54.0±5.4, 79.6±15.0, 180.1±56.2 s). Up to maximalVO2 the models over-estimated the actual VO2 response for FR (Gain: ACT 8.7±1.0, MONO 9.9±0.4, 5TD 10.3±0.3 ml O2/min/W). Up to 80% maximal VO2 the models accurately predicted the actual VO2 response across all ramp rates (Gain: ACT 10.7±1.1, 10.2±0.5, 9.2±1.0; MONO 11.0±0.8, 10.3±0.6, 9.2±0.5; 5TD 10.4±0.4, 10.2±0.3, 9.8±0.2 ml O2/min/W, values are listed SR,RR,FR). Conclusions: When variable parameter values (G and either MRT or time constant and time delay) were utilized by an integrative model, accurate estimations of the VO2 response to ramp incremental exercise were possible regardless of ramp rate (up to 80% maximal VO2). The increases in both G and MRT (or time constant) appear to balance each other to produce the quasi-linear VO2 responses.

Master of Science / Animal Sciences and Industry / Jennifer M. Bormann / Feed is the single most expensive cost related to beef cattle production. Currently a 70 d performance test is recommended for accurate calculation of efficiency. Previous research has suggested intake tests can be limited to 35 d. Objectives of this study were to estimate genetic parameters for growth and intake traits, compare two alternative indices for feed efficiency, and quantify the genetic response to selection for feed efficiency combining an intake test with two types of gain data. On–test average daily feed intake (ADFI), on-test average daily gain (ADG), and postweaning gain (PWG) records on 5,606 growing steers and heifers were obtained from the U.S. Meat Animal Research Center in Clay Center, NE. On-test ADFI and ADG data were collected from a minimum of 62 to 148 d testing days. Independent quadratic regressions were fitted for body weight on time, and on-test ADG was predicted from the resulting equations. PWG was calculated by subtracting adjusted 205-d weights from 365-d weights and dividing by 160. Genetic correlations were estimated using multiple trait animal mixed models with ADG, ADFI, and PWG for both sexes as dependent variables. The genetic correlations between ADG and PWG for both steers (0.81) and heifers (0.65) were strong. This indicates PWG is a strong proxy for ADG on-test and long test periods may not be necessary. Indices combining EBVs for ADFI and ADG and for ADFI and PWG were evaluated. For each index, the weighting of gain was arbitrarily set to 1.0 and the weighting for ADFI was the negative of the average of the intra-contemporary group ratio of mean gain divided by mean ADFI. Values were combined with EBV to compute two index values per animal. Pearson correlations for steers (0.96) and heifers (0.45) indicated a strong relationship for steers between the indices. Because more animals can be measured for intake, using PWG increases genetic progress of selection for feed efficiency by 15-17% per year. These findings support using PWG data in combination with ADFI to determine efficient animals, lessen costs, and increase annual feed efficiency genetic change.

Typescript (photocopy). / Digitized by Kansas Correctional Industries