Does the Market Punish Aggressive Experts? Evidence from Cesarean Sections

Author(s):  
David Dranove ◽  
Subramaniam Ramanarayanan ◽  
Andrew Sfekas

Abstract In many credence goods markets, a seller simultaneously diagnoses a problem and offers a recommendation to fix it. One might wonder what prevents these sellers from always exaggerating their customer’s needs. In this paper, we offer a simple explanation, namely, consumers may spurn sellers who have a reputation for such “demand inducement.” We test this explanation by examining patient choice of obstetrician in Florida. In most of the counties that we study, we find that maternity patients are significantly less likely to choose obstetricians who perform more than the expected number of cesarean sections. We address simultaneity by instrumenting for “inducement propensity” using information about the obstetrician's training. Although the instrument is weak, a series of robustness tests suggests that our findings are plausible while ruling out alternative explanations.

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Maifalinda Fatra ◽  
A Rizki ◽  
Tita Khalis Maryati

Mathematical Critical thinking is one of  mathematical abilities that must be obtained by students. Critical thinking is one of the high order thinking processes that can make concepts in student knowledge.  Students with critical thinking in mathematics learning mostly do rational activities such as interpreting information based on a particular theoretical framework, linking theory with practice, making claims and justifying it, utilizing data in support of argumentation, making relations or relationships between various ideas, asking questions, evaluating knowledge, predict, describe something, analyze, synthesize, and categorize. This study aims to analyze the effect of the Concept-Based Learning Model on the critical thingking mathematical abilities.The purpose of this research is to analyze the effect of Concept-Based Learning Model toward mathematics critical thinking ability. The method used in this research is quasi experiment by Randomize Control Group Post Test Only Design with cluster random sampling technique. Indicators of mathematics critical thinking skills measured in this study include providing simple explanations, building basic skills, concluding, making more explanations, and deciding an action. The results showed that the mathematics critical thinking ability of students in the experimental class for the five indicators that being analyze was higher than the ability of students in the control class. A fairly high difference in the indicator showed in give a simple explanation and concluding. and it means that the application of Concept-Based Learning Model significantly influences the  abilities  of students' mathematics critical thinking.


2020 ◽  
Author(s):  
Amandine Lassalle ◽  
Michael X Cohen ◽  
Laura Dekkers ◽  
Elizabeth Milne ◽  
Rasa Gulbinaite ◽  
...  

Background: People with an Autism Spectrum Condition diagnosis (ASD) are hypothesized to show atypical neural dynamics, reflecting differences in neural structure and function. However, previous results regarding neural dynamics in autistic individuals have not converged on a single pattern of differences. It is possible that the differences are cognitive-set-specific, and we therefore measured EEG in autistic individuals and matched controls during three different cognitive states: resting, visual perception, and cognitive control.Methods: Young adults with and without an ASD (N=17 in each group) matched on age (range 20 to 30 years), sex, and estimated Intelligence Quotient (IQ) were recruited. We measured their behavior and their EEG during rest, a task requiring low-level visual perception of gratings of varying spatial frequency, and the “Simon task” to elicit activity in the executive control network. We computed EEG power and Inter-Site Phase Clustering (ISPC; a measure of connectivity) in various frequency bands.Results: During rest, there were no ASD vs. controls differences in EEG power, suggesting typical oscillation power at baseline. During visual processing, without pre-baseline normalization, we found decreased broadband EEG power in ASD vs. controls, but this was not the case during the cognitive control task. Furthermore, the behavioral results of the cognitive control task suggest that autistic adults were better able to ignore irrelevant stimuli.Conclusions: Together, our results defy a simple explanation of overall differences between ASD and controls, and instead suggest a more nuanced pattern of altered neural dynamics that depend on which neural networks are engaged.


Author(s):  
M.A. Esetov , A.M. Esetov , I.V. Ramazanova

Seven cases of ultrasound diagnosis of velamentous insertion (VCI) of the umbilical cord at singleton pregnancies on 21–34 weeks of gestation are presented. The ultrasound picture two of the VIC types is presented: fixed in 5 cases and free in 2 cases. In one case the VCI was in the lower third of the uterus and the wound has been diagnosed the vasa previa. In other cases, the VCI was in middle third of the uterus. In all cases delivery was at 37–39.1 weeks of gestation. In 4 cases Cesarean sections were performed. In two of the VCI cases elective Ce sarean sections were performed for the following indications: previous Cesarean section and vasa previa. VCI can reliably be detected prenatally by gray-scale and color Doppler ultrasound. For fixed VCI located in the middle-upper of the uterus, no change in standard obstetrical management seems to be required.


2020 ◽  
Vol 19 (2) ◽  
pp. 193-200
Author(s):  
Jorge A. Carvajal ◽  
Joaquín I. Oporto

: Obesity is a worldwide public health problem, affecting at least one-third of pregnant women. One of the main problems of obesity during pregnancy is the resulting high rate of cesarean section. The leading cause of this higher frequency of cesarean sections in obese women, compared with that in nonobese women, is an altered myometrial function that leads to lower frequency and potency of contractions. In this article, the disruptions of myometrial myocytes were reviewed in obese women during pregnancy that may explain the dysfunctional labor. The myometrium of obese women exhibited lower expression of connexin43, a lower function of the oxytocin receptor, and higher activity of the potassium channels. Adipokines, such as leptin, visfatin, and apelin, whose concentrations are higher in obese women, decreased myometrial contractility, perhaps by inhibiting the myometrial RhoA/ROCK pathway. The characteristically higher cholesterol levels of obese women alter myometrial myocyte cell membranes, especially the caveolae, inhibiting oxytocin receptor function, and increasing the K+ channel activity. All these changes in the myometrial cells or their environment decrease myometrial contractility, at least partially explaining the higher rate of cesarean of sections in obese women.


1990 ◽  
Vol 55 (5) ◽  
pp. 1149-1161
Author(s):  
Jiří Závada ◽  
Václav Pechanec ◽  
Oldřich Kocián

A powerful anion effect destabilizing alkali ion-crown complex formation has been found to operate in moderately concentrated protic (H2O, CH3OH, C2H5OH) solution, following the order HO- > AcO- > Cl- > Br- > NO3- > I- > NCS-. Evidence is provided that the observed effect does not originate from ion-pairing. A simple explanation is provided in terms of concordant hydrogen bond bridges of exalted stability between the gegenions, M+···OR-H···(OR-H)n···OR-H···A-. It is proposed that encapsulation of alkali ion by the macrocyclic ligand leads to a dissipation of the cation charge density destroying its ability to participate in the hydrogen bond bridge. An opposition against the alkali ion-crown complex formation arises accordingly in the solution in dependence on strength of the hydrogen bridge; for a given cation, the hydrogen bond strength increases with increasing anion charge density from NCS- to HO-(RO-). It is pointed out, at the same time, that the observed anion effect does not correlate with the known values of activity coefficients of the individual alkali salts which are almost insensitive to anion variation under the investigated conditions. As a resolution of the apparent paradoxon it is proposed that, in absence of the macrocyclic ligand, the stabilizing (concordant) bonding between the gegenions is nearly balanced by a destabilizing (discordant) hydrogen bonding between the ions of same charge (co-ions). Intrinsic differences among the individual salts are thus submerged in protic solvents and become apparent only when the concordant bonding is suppressed in the alkali ion-crown complex formation.


2006 ◽  
Vol 32 (4) ◽  
pp. 214-220 ◽  
Author(s):  
Elizabeth J. Lindley ◽  
Nicki Thomas ◽  
Linda Hanna ◽  
Diane Walker ◽  
Elisheva Milo ◽  
...  
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