Bankruptcy exemptions, credit history, and the mortgage market.

We develop and test a model of mortgage underwriting, with particular reference to the role of credit bureau scores. In our model scores are used in a standardized fashion, which reflects the prevalence of automated underwriting in industry practice. We show that our model has implications for the debate on the effect of personal bankruptcy exemptions on secured lending. Recent literature (Berkowitz and Hynes (1999), Lin and White (2001)) has developed conflicting theories—and found conflicting results—seeking to explain how exemptions affect the mortgage market. ; By contrast, our model implies that when lenders use credit scores in a standardized manner, exemptions should be irrelevant to the mortgage underwriting decision. Merging data from a major credit bureau with the Home Mortgage Disclosure Act (HMDA) dataset, we confirm this prediction of our model. We also show that while ignoring borrower credit quality may make exemptions appear to be significant, once one controls for credit scores then exemptions have no effect on the likelihood that a mortgage application is approved. We confirm this empirically and argue that this may help explain some of the results of the previous literature.Bankruptcy ; Credit scoring systems ; Mortgage loans

Same and Different? Perspectives on the Introduction of person-Centred Care as Standard Healthcare

This thesis examines a collection of cases and situations where efforts are being made to combine and unify the concerns of person-centred care, standardization and evidence-based medicine. Person-centred care is commonly associated with efforts to improve the quality of healthcare by catering for variation and difference while evidencebased medicine and standardized guidelines aim to assure quality by reducing difference and variation. Therefore, this thesis aims to investigate the paradoxes and tensions emerging as person-centred care is introduced as standard healthcare, and the actions taken by healthcare professionals to secure this healthcare reform in practice. The analysis builds on interviews with researchers working at a research centre where a particular standardized model of personcentred care has been developed; interviews with healthcare professionals working with and introducing this standardized model; observations of healthcare professionals applying this standardized model in practice, and related documents and written materials. The thesis builds on a practice oriented approach to person-centred care and adopts a material semiotic sensibility as a theoretical foundation. This approach enables detailed analysis of the messy, relational socio-material practices of person-centred care in action. Using the notions of tinkering and articulation work, the thesis extends the basic lessons of material semiotics by underscoring the importance of reciprocity - interrogating how inventive practices act back on and reshape tools, technologies and standards of person-centred care. Empirically the thesis encompasses four studies. Paper I examines the mundane technologies of person-centred care, the scripts and values inscribed in these technologies and the tinkering needed to balance and bring together potentially contrasting values in practice. Paper II investigates how person-centred care and evidence-based medicine are interwoven in practice and the tensions that emerge when a randomized controlled trial is used to evaluate personcentred care. Paper III draws on the notions of articulation work and invisible work to analyse the efforts involved in sustaining a particular standardized framework of person-centred care. Paper IV identifies the tenacious assumptions embedded in a standardized model of person-centred care and the challenges emerging when this model is introduced in diverse settings. Based on these studies I argue that while person-centred care is often advocated as the anti-thesis to standardized biomedicine this relationship is more complex. The studies in this thesis address attempts to develop a model of healthcare that is at once the same for all patients, yet also different by catering to each individual patient as a unique person. However, modelling care in this way is not without its challenges. One of the foremost challenges of making care recognizing the patient as a person into standard healthcare concerns how this person is actually imagined and enacted. By insisting on particular routines to be followed and specific values to be recognized particular versions of person-centred care risk embedding problematic assumptions of their own. These assumptions are very similar to those it aims to move beyond in the first place. The standardized model of person-centred care, as well as the tensions and challenges it gives rise to, are negotiated and managed in a variety of ways. Caregivers are obliged to make adaptions, translations and become creative mediators in order to enable the standardized model of person-centred care to hold together. They also have to coordinate different tasks, perform complex activities for which they have little prior training, and creatively interpret incomplete instructions in order to compensate for shortfalls in information. However, the thesis concludes that things could be otherwise if person-centred care was able to learn from material semiotics. Instead of conceiving person-centred care as something that has to be implemented and safeguarded in practice, an alternative vision would be to develop person-centred care in its local organizational complexity and thereby transform it from being something ready-made, which care professionals have to adhere to, to something that is an outcome of experimental interventions

Artfilms, Handicrafts and Other Cultural Goods: The Case for Subsidy

Though widespread, the practice of public subsidies for cultural activity lacks a rigorous and consistent economic rationale. We analyze a canonical market structure that characterizes much cultural activity: the competition of mass-produced goods with heterogeneous non- standardized goods that are imperfect substitutes. We analyze several types of market failure: uncertainty about preferences (we do not know what we like, and we do not know what we might like in the future); endogeneity of preferences (we like what our neighbors talk about, and we like what we're accustomed to); and externalities associated with production (future production costs are determined by current production). The model provides a basis for cultural subsidies to promote social welfare and economic development.

Standardized Competencies for Parenteral Nutrition Prescribing: The American Society for Parenteral and Enteral Nutrition Model

Parenteral nutrition (PN) provision is complex, as it is a high-alert medication and prone to a variety of potential errors. With changes in clinical practice models and recent federal rulings, the number of PN prescribers may be increasing. Safe prescribing of this therapy requires that competency for prescribers from all disciplines be demonstrated using a standardized process. A standardized model for PN prescribing competency is proposed based on a competency framework, the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.)–published interdisciplinary core competencies, safe practice recommendations, and clinical guidelines. This framework will guide institutions and agencies in developing and maintaining competency for safe PN prescription by their staff

Spatial autocorrelation approaches to testing residuals from least squares regression

In statistics, the Durbin-Watson test is always employed to detect the presence of serial correlation of residuals from a least squares regression analysis. However, the Durbin-Watson statistic is only suitable for ordered time or spatial series. If the variables comprise cross-sectional data coming from spatial random sampling, the Durbin-Watson will be ineffectual because the value of Durbin-Watson's statistic depends on the sequences of data point arrangement. Based on the ideas from spatial autocorrelation, this paper presents two new statistics for testing serial correlation of residuals from least squares regression based on spatial samples. By analogy with the new form of Moran's index, an autocorrelation coefficient is defined with a standardized residual vector and a normalized spatial weight matrix. Then on the analogy of the Durbin-Watson statistic, a serial correlation index is constructed. As a case, the two statistics are applied to the spatial sample of 29 China's regions. These results show that the new spatial autocorrelation model can be used to test the serial correlation of residuals from regression analysis. In practice, the new statistics can make up for the deficiency of the Durbin-Watson test.Comment: 27 pages, 4 figures, 5 tables, 2 appendice

Experience of Robotic Exoskeleton Use at Four Spinal Cord Injury Model Systems Centers

Background and Purpose: Refinement of robotic exoskeletons for overground walking is progressing rapidly. We describe clinicians\u27 experiences, evaluations, and training strategies using robotic exoskeletons in spinal cord injury rehabilitation and wellness settings and describe clinicians\u27 perceptions of exoskeleton benefits and risks and developments that would enhance utility. Methods: We convened focus groups at 4 spinal cord injury model system centers. A court reporter took verbatim notes and provided a transcript. Research staff used a thematic coding approach to summarize discussions. Results: Thirty clinicians participated in focus groups. They reported using exoskeletons primarily in outpatient and wellness settings; 1 center used exoskeletons during inpatient rehabilitation. A typical episode of outpatient exoskeleton therapy comprises 20 to 30 sessions and at least 2 staff members are involved in each session. Treatment focuses on standing, stepping, and gait training; therapists measure progress with standardized assessments. Beyond improved gait, participants attributed physiological, psychological, and social benefits to exoskeleton use. Potential risks included falls, skin irritation, and disappointed expectations. Participants identified enhancements that would be of value including greater durability and adjustability, lighter weight, 1-hand controls, ability to navigate stairs and uneven surfaces, and ability to balance without upper extremity support. Discussion and Conclusions: Each spinal cord injury model system center had shared and distinct practices in terms of how it integrates robotic exoskeletons into physical therapy services. There is currently little evidence to guide integration of exoskeletons into rehabilitation therapy services and a pressing need to generate evidence to guide practice and to inform patients\u27 expectations as more devices enter the market. Background and Purpose: Refinement of robotic exoskeletons for overground walking is progressing rapidly. We describe clinicians\u27 experiences, evaluations, and training strategies using robotic exoskeletons in spinal cord injury rehabilitation and wellness settings and describe clinicians\u27 perceptions of exoskeleton benefits and risks and developments that would enhance utility. Methods: We convened focus groups at 4 spinal cord injury model system centers. A court reporter took verbatim notes and provided a transcript. Research staff used a thematic coding approach to summarize discussions. Results: Thirty clinicians participated in focus groups. They reported using exoskeletons primarily in outpatient and wellness settings; 1 center used exoskeletons during inpatient rehabilitation. A typical episode of outpatient exoskeleton therapy comprises 20 to 30 sessions and at least 2 staff members are involved in each session. Treatment focuses on standing, stepping, and gait training; therapists measure progress with standardized assessments. Beyond improved gait, participants attributed physiological, psychological, and social benefits to exoskeleton use. Potential risks included falls, skin irritation, and disappointed expectations. Participants identified enhancements that would be of value including greater durability and adjustability, lighter weight, 1-hand controls, ability to navigate stairs and uneven surfaces, and ability to balance without upper extremity support. Discussion and Conclusions: Each spinal cord injury model system center had shared and distinct practices in terms of how it integrates robotic exoskeletons into physical therapy services. There is currently little evidence to guide integration of exoskeletons into rehabilitation therapy services and a pressing need to generate evidence to guide practice and to inform patients\u27 expectations as more devices enter the market

A practice-related risk score (PRS): a DOPPS-derived aggregate quality index for haemodialysis facilities

Background. The Dialysis Outcomes and Practice Patterns Study (DOPPS) database was used to develop and validate a practice-related risk score (PRS) based on modifiable practices to help facilities assess potential areas for improving patient care. Methods. Relative risks (RRs) from a multivariable Cox mortality model, based on observational haemodialysis (HD) patient data from DOPPS I (1996-2001, seven countries), were used. The four practices were the percent of patients with Kt/V >= 1.2, haemoglobin >= 11 g/dl (110 g/l), albumin >= 4.0 g/dl (40g/l) and catheter use, and were significantly related to mortality when modelled together. DOPPS II data (2002-2004, 12 countries) were used to evaluate the relationship between PRS and mortality risk using Cox regression. Results. For facilities in DOPPS I and II, changes in PRS over time were significantly correlated with changes in the standardized mortality ratio (SMR). The PRS ranged from 1.0 to 2.1. Overall, the adjusted RR of death was 1.05 per 0.1 points higher PRS (P < 0.0001). For facilities in both DOPPS I and II (N = 119), a 0.2 decrease in PRS was associated with a 0.19 decrease in SMR (P = 0.005). On average, facilities that improved PRS practices showed significantly reduced mortality over the same time frame. Conclusions. The PRS assesses modifiable HD practices that are linked to improved patient survival. Further refinements might lead to improvements in the PRS and will address regional variations in the PRS/mortality relationship

Maximin and Bayesian optimal designs for regression models

For many problems of statistical inference in regression modelling, the Fisher information matrix depends on certain nuisance parameters which are unknown and which enter the model nonlinearly. A common strategy to deal with this problem within the context of design is to construct maximin optimal designs as those designs which maximize the minimum value of a real valued (standardized) function of the Fisher information matrix, where the minimum is taken over a specified range of the unknown parameters. The maximin criterion is not differentiable and the construction of the associated optimal designs is therefore difficult to achieve in practice. In the present paper the relationship between maximin optimal designs and a class of Bayesian optimal designs for which the associated criteria are differentiable is explored. In particular, a general methodology for determining maximin optimal designs is introduced based on the fact that in many cases these designs can be obtained as weak limits of appropriate Bayesian optimal designs. --maximin optimal designs,Bayesian optimal designs,nonlinear regression models,parameter estimation,least favourable prior

A Double Machine Learning Approach to Estimate the Effects of Musical Practice on Student's Skills

This study investigates the dose-response effects of making music on youth development. Identification is based on the conditional independence assumption and estimation is implemented using a recent double machine learning estimator. The study proposes solutions to two highly practically relevant questions that arise for these new methods: (i) How to investigate sensitivity of estimates to tuning parameter choices in the machine learning part? (ii) How to assess covariate balancing in high-dimensional settings? The results show that improvements in objectively measured cognitive skills require at least medium intensity, while improvements in school grades are already observed for low intensity of practice