A Data mining approach to indirect inference

Consider a model with parameter phi, and an auxiliary model with parameter theta. Let phi be a randomly sampled from a given density over the known parameter space. Monte Carlo methods can be used to draw simulated data and compute the corresponding estimate of theta, say theta_tilde. A large set of tuples (phi, theta_tilde) can be generated in this manner. Nonparametric methods may be use to fit the function E(phi|theta_tilde=a), using these tuples. It is proposed to estimate phi using the fitted E(phi|theta_tilde=theta_hat), where theta_hat is the auxiliary estimate, using the real sample data. This is a consistent and asymptotically normally distributed estimator, under certain assumptions. Monte Carlo results for dynamic panel data and vector autoregressions show that this estimator can have very attractive small sample properties. Confidence intervals can be constructed using the quantiles of the phi for which theta_tilde is close to theta_hat. Such confidence intervals are found to have very accurate coverage.

Approche des oedèmes du membre supérieur liés à une occlusion de la veine sous-clavière située en aval d'une fistule artério-veineuse [Approach to upper limb edema secondary to subclavian vein occlusion situated distal to an arteriovenous fistula]

AIM OF THE STUDY: To analyse the course of upper limb edema in patients with an arteriovenous fistula used for dialysis and to analyse the available therapeutic options. STUDY DESIGN: Retrospective study of patients with this type of edema, who were treated in our institution from 1992 to 1996. PATIENTS AND METHODS: Seven consecutive patients with an arterioveinous fistula treated for edema of the upper extremity, were reviewed. The fistula was created at the elbow in 6 patients and at the forearm in 1. The edema appeared immediately after operation in 4 patients and after a delay in 3 patients. Stenosis (3 patients) or occlusion (2 patients) of the subclavian vein was documented in 5 patients who were investigated by angiography. RESULTS: The edema regressed spontaneously in 4 patients because collaterals developed in 3 patients, and the fistula thrombosed in 1 patient. Surgical intervention allowed regression of the edema in the other 3 patients: excessive output of the fistula was reduced in 2 patients and an axillojugular bypass was performed in 1 patient. The fistula remained effective in 6 patients. Another fistula was performed on the contralateral arm in 1 patient. CONCLUSION: Non-operative management is recommended in patients who develop edema immediately after creation of the fistula, because spontaneous regression is likely. Measures aimed at reducing the output of the fistula or enhancing the venous capacities of the arm are required when edema appears at a later stage. The fistula can be saved in the majority of cases.

Diagnostic approach to pupillary abnormalities.

PURPOSE OF REVIEW: This article presents an overview of the common and various kinds of pupillary disorders that can be encountered in an outpatient setting. RECENT FINDINGS: The dorsal midbrain is a site where lesions may produce either an afferent or an efferent pupillary defect. The classic pupillary syndrome secondary to a dorsal midbrain lesion is bilateral light-near dissociation. Another recognized deficit is bilateral mydriasis. Recent reports have documented unilateral mydriasis, unilateral light-near dissociation, and a relative afferent pupillary defect without visual loss in association with lesions of the dorsal midbrain. These are rare syndromes. SUMMARY: Careful history and examination can often identify and localize the pupillary disorder, as well as guide appropriate evaluation.

The GYRO System: a Recommended Approach to More Transparent Documentation

The GYRO documentation system offers a simple and efficient method for a friction ridge examiner to document the analysis and comparison stages of the ACE-V process. GYRO uses a color-coding system to convey the analyst's degree of confidence in the existence of a feature and the degree of variation to which that feature max appear in a corresponding exemplar print. We also explore the benefits and utility of the PiAnoS software, which bears some similarity to GYRO, but with added tools.

An epidemiological and clinical approach to adolescent suicide. A comparison between suicidal and non-suicidal clinical groups in a health foundation center for French students.

Suicidal behaviour among young people represents a major public health problem. This study seeks to compare the major sociological, clinical, schooling and family features of suicidal and non-suicidal subgroups of adolescents hospitalised in the Health Foundation Center for French Students of neufmoutiers en Brie (France). All these adolescents suffered from the severe mental disorders. The adolescents from the suicidal subgroup presented significantly fewer psychoses and more mood disorders than those of the non-suicidal subgroup. Half of the patients from the suicidal subgroup presented some features of personality disorders, mostly borderline personality disorders. Nevertheless, their global functioning was more frequently improved between admission and discharge than was the case for the non-suicidal group.

A low stringency polymerase chain reaction approach to the identification of Biomphalaria glabrata and B. tenagophila, intermediate snail hosts of Schistosoma mansoni in Brazil

The low stringency-polymerase chain reaction (LS-PCR) with a pair of specific primers for the amplification of the 18S rRNA gene was evaluated as a means of differentiating between the two Schistosoma mansoni intermediate host species in Brazil: Biomphalaria glabrata and B. tenagophila. Individual snails obtained from different states of Brazil were used and the amplification patterns obtained showed a high degree of genetic variability in these species. Nevertheless, 4 and 3 clearly defined specific diagnostic bands was observed in individuals from B. glabrata and B. tenagophila respectively. The detection of snail specific diagnostic bands suggests the possibility of reliable species differentiation at the DNA level using LS-PCR.

A Laboratory-based Approach to Biological Control of Snails

Development of Schistosoma mansoni in the intermediate host Biomphalaria glabrata is influenced by a number of parasite and snail genes. Understanding the genetics involved in this complex host/parasite relationship may lead to an often discussed approach of introducing resistant B. glabrata into the field as a means of biological control for the parasite. For the snail, juvenile susceptibility to the parasite is controlled by at least four genes, whereas one gene seems to be responsible for adult nonsusceptibility. Obtaining DNA from F2 progeny snails from crosses between parasite-resistant and-susceptible snails, we have searched for molecular markers that show linkage to either the resistant or susceptible phenotype. Both restriction fragment length polymorphism (RFLP) and random amplified polymorphic DNA (RAPD) approaches have been used. To date, using a variety of snail and heterologous species probes, no RFLP marker has been found that segregates with either the resistant or susceptible phenotype in F2 progeny snails. More promising results however have been found with the RAPD approach, where a 1.3 kb marker appears in nearly all resistant progeny, and a 1.1 kb marker appears in all susceptible progeny

An Experimental Approach to the Pathogenesis of "Pipestem" Fibrosis (Symmers' Fibrosis of the Liver)

Pathogenesis of schistosomal hepatic fibrosis ("pipestem" fibrosis of the liver) was investigated by means of the murine model. Although worm load appears as the main pathogenetic factor, alone it is not sufficient to produce that characteristic lesion. By comparing the findings in animals with heavy and prolonged Schistosoma mansoni infection, which developed or not" pipestem" fibrosis, it was observed that the lesion was more frequent in intact animals than in the splenectomized one. However, the size of the spleen, the number of recovered worms, the number of eggs per gram of liver tissue, the level of serum idiotype and anti-idiotype antibodies, the size and volume of periovular granulomas formed in the liver, all that failed to show statistically significant differences between the two groups. After analysing all these data, other factors, that apparently have been hitherto negleted, rested to explain the findings. Among them, the timing and sequence of the egg-induced intrahepatic vascular changes seemed crucial. The sequential development of intrahepatic portal vein obstruction, followed by the opening of periportal collateral veins and the continous arrival of schistosome eggs going to be lodged into the latter, appeared as essential steps in the pathogenesis of "pipestem" fibrosis

Physical activity in 22 African countries: results from the World Health Organization STEPwise approach to chronic disease risk factor surveillance.

BACKGROUND: Baseline physical activity data are needed to effectively plan programs and policies to prevent noncommunicable diseases, but for many African countries these data are lacking. PURPOSE: To describe and compare levels and patterns of physical activity among adults across 22 African countries. METHODS: Data from 57,038 individuals from 22 countries (11 national and 11 subnational samples) that participated in the STEPwise approach to chronic disease risk factor surveillance (2003-2009) were analyzed in 2010. The validated Global Physical Activity Questionnaire (GPAQ) was used to assess days and duration of physical activity at work, for transport, and during leisure time in a typical week. RESULTS: Overall, 83.8% of men and 75.7% of women met WHO physical activity recommendations (at least 150 minutes of moderate activity per week or equivalent). Country prevalence ranged from 46.8% (Mali) to 96.0% (Mozambique). Physical activity, both at work and for transport, including walking, had large contributions to overall physical activity, while physical activity during leisure time was rare in the analyzed countries. CONCLUSIONS: Physical activity levels varied greatly across African countries and population subgroups. Leisure time activity was consistently low. These data will be useful to inform policymakers and to guide interventions to promote physical activity.

A logistic regression approach to estimating customer profit loss due to lapses in insurance

This article focuses on business risk management in the insurance industry. A methodology for estimating the profit loss caused by each customer in the portfolio due to policy cancellation is proposed. Using data from a European insurance company, customer behaviour over time is analyzed in order to estimate the probability of policy cancelation and the resulting potential profit loss due to cancellation. Customers may have up to two different lines of business contracts: motor insurance and other diverse insurance (such as, home contents, life or accident insurance). Implications for understanding customer cancellation behaviour as the core of business risk management are outlined.

Syndrome de Sjögren: enfin une nouvelle approche de traitement [Sjögren's syndrome: a new approach to treatment].

Södgren's syndrome treatment has essentially been based on symptomatic approach and has been of limited efficacy. Novel biological therapies targeting B cells, a key player in the pathophysiology of the syndrome, have recently been tested in controlled clinical trials and raise the hope of improving glandular and extraglandular manifestations of Söigren's syndrome.