Prescription Fraud detection via data mining : a methodology proposal

Ankara : The Department of Industrial Engineering and the Institute of Engineering and Science of Bilkent University, 2009.Thesis (Master's) -- -Bilkent University, 2009.Includes bibliographical references leaves 61-69Fraud is the illegitimate act of violating regulations in order to gain personal profit. These kinds of violations are seen in many important areas including, healthcare, computer networks, credit card transactions and communications. Every year health care fraud causes considerable amount of losses to Social Security Agencies and Insurance Companies in many countries including Turkey and USA. This kind of crime is often seem victimless by the committers, nonetheless the fraudulent chain between pharmaceutical companies, health care providers, patients and pharmacies not only damage the health care system with the financial burden but also greatly hinders the health care system to provide legitimate patients with quality health care. One of the biggest issues related with health care fraud is the prescription fraud. This thesis aims to identify a data mining methodology in order to detect fraudulent prescriptions in a large prescription database, which is a task traditionally conducted by human experts. For this purpose, we have developed a customized data-mining model for the prescription fraud detection. We employ data mining methodologies for assigning a risk score to prescriptions regarding Prescribed Medicament- Diagnosis consistency, Prescribed Medicaments’ consistency within a prescription, Prescribed Medicament- Age and Sex consistency and Diagnosis- Cost consistency. Our proposed model has been tested on real world data. The results we obtained from our experimentations reveal that the proposed model works considerably well for the prescription fraud detection problem with a 77.4% true positive rate. We conclude that incorporating such a system in Social Security Agencies would radically decrease human-expert auditing costs and efficiency.Aral, Karca DuruM.S

Investigation of helium isotope variations of alkaline volcanic rocks In Osmaniye Region Turkey

The noble gases, in particular helium isotopes, provide valuable information on the mantle source of recentbasaltic volcanism, especially when linked to trace elements and radiogenic isotopes. Although the alkalinevolcanics in the Kütahya region have been studied in detail by several works by means of trace element variations,radiogenic dating and isotope systematics, noble gas isotope compositions that could significantly contribute todynamics of volcanism have not been investigated yet. In this study which aims to fill the deficiency of such data,helium isotope compositions of olivine-basalts in Kütahya region are measured.In this study we report helium isotope compositions of olivine from basalts. In olivine-basalts in alkalinevolcanic rocks from the Kütahya region, western Turkey, are investigated. 3He/4He range from 3.0 to 5.19 Ra.These low helium isotope values are most probably indicative of a lithospheric mantle source. Kütahya alkalinevolcanics are enriched in incompatible elements and show prominent negative Ti, Nd and Ta anomaly. Primitivemantle normalized trace element concentration patterns clearly display continental crustal contamination.Chemical compositions and helium isotope systematics imply contribution of a lithospheric mantle source andcontamination of continental crust in the genesis of the Kütahya alkaline lava

Environmental and climatic signals from stable isotopes in Anatolian tree rings, Turkey

Dendrochronological and oxygen-carbon isotopic analysis was conducted on tree rings collected at two different elevations from three different regions in western Anatolia, Turkey. Tree rings were sampled from Anatolian black pines (Pinus nigra Arn. subsp. pallasiana (Lamb.) Holmboe) of at least 200 years old through an N-S transect covering Bolu-Mengen (north), Kutahya-Simav, and Antalya-Alanya (south) forests. Cellulose was extracted from 5-year blocks of tree rings from lower to upper altitudes in each region. Dendrochronological site chronologies were built for each of the 6 sites, and response to climate was evaluated. The long-term delta C-13 chronologies comprising the period 1800-2008 strongly decline by an average of 2.5aEuro degrees from the mid-twentieth century, which corresponds with the commencement of industrialization in Turkey. Oxygen isotope (delta O-18) time series show dominantly low undulations, although some high-frequency variations of up to 6aEuro degrees are also observed. As a result of latitude and continent effects, oxygen isotope values of tree rings show an average of 3aEuro degrees increase from south (Antalya) to the north (Bolu). Correlations between carbon isotope ratios yield high positive values indicating that industrial pollution exerts a major control on the delta C-13 systematics of the studied trees. Corrected delta C-13 ratios are mostly represented by strong positive responses to variations in temperature and precipitation, whereas delta O-18 and summer temperature/precipitation are negatively correlated. Tree-ring widths and delta O-18 display similar responses to the temperature and sensitivity to the climatic impact of historic volcanic eruptions, and changes in the solar irradiance record are also detected in other high-resolution paleoclimate archives for the region