Suchergebnisse

We extend the Baye and Morgan (2001) model to study competition between price comparison sites in the information market on the internet. We identify one symmetric sub-game perfect Nash equilibrium in which (1) price comparison sites set the same advertising fees; (2) the same proportion of consumers subscribe to each site; (3) each firm mixes between advertising on all sites and not advertising; and (4) advertised prices are dispersed. The introduction of additional price comparison sites may reduce social welfare and joint profits of price comparison sites. In the equilibrium with each consumer subscribing to one site, as the number of price comparison sites goes to infinity, the information market approaches that without price comparison sites.

Abstract
Purpose
Breath profiling has gained importance in recent years as it is a non-invasive technique to identify biomarkers for various diseases. Breath profiling of abnormal liver function in individuals for identifying potential biomarkers in exhaled breath could be a useful diagnostic tool. The objective of this study was to identify potential biomarkers in exhaled breath that remain stable and consistent during different physiological states, including rest and brief workouts, intending to develop a non-invasive diagnostic tool for detecting abnormal liver function.

Method
Our study employed a gas chromatography and mass-spectrometer quantified dataset for analysis. Machine learning techniques, including feature selection and model training, were used to rank and evaluate potential biomarkers' contributions to the model's performance. Statistical methods were applied to filter significant and consistent biomarkers. The final selected biomarkers were iterated for all possible combinations using machine learning algorithms to determine their accuracy range. Furthermore, classification models were used to evaluate the performance metrics of the biomarkers and compare models.

Result
The final selected biomarkers, including 2-Myristynoyl Pantetheine, Pterin-6 Carboxylic Acid, Methyl Mercaptan, N-Acetyl Cysteine, and Butyric Acid, exhibited stable levels in exhaled breath during different physiological states. They showed high accuracy and precision in detecting abnormal liver function. Our machine learning models achieved an accuracy rate ranging from 0.7 to 0.95 in all conditions, with precision, recall, prediction probability, and a 95% confidence interval ranging from 0.84 to 0.94, using various combinations of these biomarkers.

Conclusion
Our statistical and machine learning analysis identified significant and potential biomarkers that contribute to the detection of abnormal liver function. These biomarkers were consistent across different physiological states of the body in both patient and healthy groups. The use of breath samples and feature selection machine learning methods proved to be an accurate and reliable approach for identifying these biomarkers. Our findings provide valuable insights for future research in this field and can inform the development of non-invasive and cost-effective diagnostic tests for liver disease.

AbstractManuscript TypeEmpiricalResearch Question/IssueThis study investigates the influence of CEO characteristics on internal control quality in the U.S.Research Findings/InsightsUsing a sample of 4,374 ExecuComp non‐financial firms, we find that CEO entrenchment and age are significantly associated with a material internal control weakness disclosure (MW) under Sarbanes‐Oxley Section 404 (SOX 404). Our results demonstrate that entrenchment and age may affect CEOs' behavior in response to the SOX 404 internal control requirements.Theoretical/Academic ImplicationsThis study provides empirical support for the influence of CEO characteristics on material internal control weakness. As a result, the effects of internal control mechanisms are likely to be decreased in firms with entrenched and younger CEOs, consistent with entrenchment theory.Practitioner/Policy ImplicationsThis study offers insights to regulators and lawmakers interested in the effects of CEO characteristics on internal control weakness. Importantly, it points out that CEO entrenchment and age are likely to affect the strength of internal control mechanisms.