Expectations in Micro Data: Rationality Revisited

An increasing number of longitudinal data sets collect expectations information regarding a variety of future individual level events and decisions, providing researchers with the opportunity to explore expectations over micro variables in detail. We present a theoretical framework and an econometric methodology to use that type of information to test the Rational Expectations (RE) hypothesis in models of individual behavior. This RE assumption at the micro level underlies a majority of the research in applied fields in economics, and it is the common foundation of most work in dynamic models of individual behavior. We present tests of three different types of expectations using two different panel data sets that represent two very different populations. In all three cases we cannot reject the RE hypothesis. Our results support a wide variety of models in economics, and other disciplines, that assume rational behavior.Rational Expectations, Retirement, Longevity, and Education Expectations, Instrumental Variables, Sample Selection.

Expectations in Micro Data: Rationality Revisited

An increasing number of longitudinal data sets collect expectations information regarding a variety of future individual level events and decisions, providing researchers with the opportunity to explore expectations over micro variables in detail. We provide a theoretical framework and an econometric methodology to use that type of information to test the Rational Expectations hypothesis in models of individual behavior, and present tests using two different panel data sets.

Augmented Reality for Cryoablation Procedures

International audienceCryotherapy is a rapidly growing minimally invasive technique for the treatment of different kinds of tumors, such as breast cancer, renal and prostate cancer. Several hollow needles are percutaneously inserted in the target area under image guidance and a gas (usually argon) is then decompressed inside the needles. Based on the Thompson-Joule principle, the temperature drops drown and a ball of ice crystals forms around the tip of each needle. Radiologists rely on the geometry of this iceball (273K), visible on computer tomographic (CT) or magnetic resonance (MR) images, to assess the status of the ablation. However, cellular death only occurs when the temperature falls below 233K. The complexity of the procedure therefore resides in planning the optimal number, position and orientation of the needles required to treat the tumor, while avoiding any damage to the surrounding healthy tissues.This planning is currently done qualitatively, based on experience, and can take several hours, with a result that is often different from the expected one. To solve this important limitation of cryotherapy, a few planning systems have been proposed in the literature. Currently, commercial systems are nearly non existent, and emerging tools are limited to a visualization of the isotherms obtained for each needle in ideal conditions (usually in a gel). They do not account for any influence of the soft tissue properties, the presence of blood vessels, or the combined effect of multiple needles. As a consequence, large safety margins over 5mm are defined.To address this challenge, our method extracts information from medical images (CT or MR) and allows to assess different strategies with an augmented visualization of the resulting iceball and the associated isotherms

Total Factor Productivity and the Role of Entrepreneurship

Total factor productivity of twenty OECD countries for a recent period (1971-2002) is explained using six different models based on the established literature. Traditionally, entrepreneurship is not dealt with in these models. In the present paper it is shown that – when this variable is added - in all models there is a significant influence of entrepreneurship while the remaining effects mainly stay the same. Entrepreneurship is measured as the business ownership rate (number of business owners per workforce) corrected for the level of economic development (GDP per capita)

Health Status, Insurance, and Expenditures in the Transition from Work to Retirement

This paper analyzes the dynamics of health insurance coverage, health expenditures, and health status in the decade expanding from 1992 to 2002, for a cohort of older Americans. We follow 13,594 individuals interviewed in Waves 1 to 6 of the Health and Retirement Study, most of whom were born between 1930 and 1940, as they transition from work into retirement. Although this “depression cohort” is by and large fairly well prepared for retirement in terms of pension coverage and savings, we identify significant gaps in their health insurance coverage, especially among the most disadvantaged members of this cohort. We find that government health insurance programs—particularly Medicare and Medicaid—significantly reduce the number of individuals who are uninsured and the risks of large out of pocket health care costs. However, prior to retirement large numbers of these respondents were uninsured, nearly 18% at the first survey in 1992. Moreover, a much larger share, about 55% of this cohort, are transitorily uninsured, that is, they experience one or more spells, lasting from several months to several years, without health insurance coverage. We also identify a much smaller group of persistently uninsured individuals, and show that this group has significantly less wealth, and higher rates of poverty, unemployment, and health problems, disability, and higher mortality rates than the rest of the members of the cohort under study. We provide evidence that lack of health insurance coverage is correlated with reduced utilization of health care services; for example, respondents with no health insurance visit the doctor one fourth as often as those with private insurance and are also more likely to report declines in health status. We also analyze the components of out of pocket health care costs, and show that prescription drug costs constituted a rapidly rising share of the overall cost of health care during the period of analysis.

Total factor productivity and the role of entrepreneurship

The absence of evidence in the scholarly literature for a tested long-term relationship between entrepreneurship and economic growth is at odds with the importance attributed to entrepreneurship in the policy arena. The present paper addresses this absence, introducing entrepreneurship using four different and accepted models explaining the total factor productivity of twenty OECD countries with data for the period 1969–2010. Traditionally, entrepreneurship is not addressed in these models. We show that in all models—as well as a joint one—entrepreneurship has a significant influence while the remaining effects largely stay the same. Entrepreneurship is measured as the business ownership rate (number of business owners per workforce) corrected for the level of economic development (GDP per capita)

Do psychosocial factors predict the persistence of shoulder pain?

Background and aims: The key mechanisms involved in the development of persistent shoulder pain are still not clearly understood. Even if psychosocial factors have been shown to be associate with chronicization of musculoskeletal pain, few studies have explored the impact of these factors in the persistence of rotator cuff related shoulder pain (RCRSP). The aim of this study was to identify the psychosocial risk factors associated with persistence of pain in individuals with RCRSP after an education program targeting shoulder pain self-management. Methods: Fifty-nine participants with persistent RCRSP completed this study (43.9±11.5years; 61%women; 70% had pain duration > 1year). Using the RedCap web application, all participants filled questionnaires covering a biopsychosocial spectrum: Brief Resilience Scale (BRS), Perceived Stress Scale (PSS-10), Disabilities of the Arm, Shoulder, and Hand Questionnaire (QuickDASH), Patient-Health Questionnaire – 9 (PHQ-9), General Anxiety Disorder – 7 (GAD-7), Pain Catastrophizing Scale (PCS), Pain Self-Efficacy Questionnaire (PSEQ) and Multidimensional Scale of Perceived Social Support (MSPSS). Thereafter, participants took part in an educational program aimed at promoting self-management of shoulder pain that included two meetings with a physiotherapist. After 3 months, participants filled the QuickDASH and, based on their scores, were classified as having persistent shoulder pain (score>11) or as recovered (score=0-11). Results: The symptoms of 24 participants (~41%) were considered resolved at 3 months. A binomial logistic regression demonstrated that only PSEQ was associated with symptoms resolution (p=.04). Lower level of self-efficacy was associated with persistent pain at 3 months (Odds Ratio= 1.08 95%Confidence Interval (CI): 1.00, 1.17. No variables predicted persistent RCRSP. Conclusions: Pain self-efficacy was the most important factor in avoiding the development of persistent RCRSP.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

STATIC AND DYNAMIC CHARACTERISTICS OF COMPOSITE ONE·PIECE HOCKEY STICKS

The purpose of this study was to evaluate the differE:nces in slatic and dynamic characteristics of one-piece composite hockey sticks of different brands and models. Earlier studies had only evaluated two-pieces sticks of different materials. Even if some static results present many similarities with those disclosed by earlier researchers, torsion tests have demonstrated one-piece composite sticks to be much more torsion resistant than two-pieces and wooden sticks. Furthermore, dynamic evaluations have disclosed very interesting puck-blade interactions, including multiple puck-blade impacts in actual slap shot situations

Repetitive transcranial magnetic stimulation alone and in combination with motor control exercise for the treatment of individuals with chronic non-s­pecific ­low­ back­ pain­ (ExTraStim­ trial): study protocol for a randomised controlled trial

Introduction While multiple pharmacological and non-pharmacological interventions treating chronic non-specific low back pain (CLBP) are available, they have been shown to produce at best modest effects. Interventions such as repetitive transcranial magnetic stimulation (rTMS), a form of non-invasive brain stimulation, have exhibited promising results to alleviate chronic pain. However, evidence on the effectiveness of rTMS for CLBP is scarce due to limited rigorous clinical trials. Combining rTMS with motor control exercises (MCE) may help to address both central and nociceptive factors contributing to the persistence of LBP. The primary aim of this randomised controlled trial is to compare the effectiveness of a combination of rTMS and MCE to repeated rTMS sessions alone, sham rTMS and a combination of sham rTMS and MCE on pain intensity. Methods and analysis One hundred and forty participants (35/group) with CLBP will be randomised into four groups (active rTMS+MCE, sham rTMS+MCE, active rTMS and sham rTMS) to receive 10 sessions of their allocated intervention. The primary outcome will be the pain intensity, assessed at baseline, 4, 8, 12 and 24 weeks. Secondary outcomes will include disability, fear of movement, quality of life and patient global rating of change. Ethics and dissemination Ethics approval was obtained from the Comité d’éthique de la recherche sectoriel en réadaptation et intégration sociale, CIUSS de la Capitale Nationale in June 2019 (#2020–1844 – CER CIUSSS-CN). The results of the study will be submitted to a peer- reviewed journal and scientific meetings. Trial registration number NCT04555278