Supplier selection with support vector regression and twin support vector regression

Tedarikçi seçimi sorunu son zamanlarda literatürde oldukça ilgi görmektedir. Güncel literatür, yapay zeka tekniklerinin geleneksel istatistiksel yöntemlerle karşılaştırıldığında daha iyi bir performans sağladığını göstermektedir. Son zamanlarda, destek vektör makinesi, araştırmacılar tarafından çok daha fazla ilgi görse de, buna dayalı tedarikçi seçimi çalışmalarına pek sık rastlanmamaktadır. Bu çalışmada, tedarikçi kredi endeksini tahmin etmek amacıyla, destek vektör regresyon (DVR) ve ikiz destek vektör regresyon (İDVR) teknikleri kullanılmıştır. Pratikte, tedarikçi verisini içeren örneklemler sayıca oldukça yetersizdir. DVR ve İDVR daha küçük örneklemlerle analiz yapmaya uyarlanabilir. Tedarikçilerin belirlenmesinde DVR ve İDVR yöntemlerinin tahmin kesinlikleri karşılaştırılmıştır. Gerçek örnekler İDVR yönteminin DVR yöntemine kıyasla üstün olduğunu göstermektedir.Suppliers’ selection problem has attracted considerable research interest in recent years. Recent literature show that artificial intelligence techniques achieve better performance than traditional statistical methods. Recently, support vector machine has received much more attention from researchers, while studies on supplier selection based on it are few. In this paper, we applied the support vector regression (SVR) and twin support vector regression (TSVR) techniques to predict the supplier credit index. In practice, the suppliers’ samples are very insufficient. SVR and TSVR are adaptive to deal with small samples. The prediction accuracies for SVR and TSVR methods are compared to choose appropriate suppliers. The actual examples illustrate that TSVR methods are superior to SVR

Relationship between export capabilities and competitive advantage: An empirical investigation on Turkish exporters

İhracat literatürde firmaların uluslararası pazarlara girmelerini sağlayan en basit stratejik seçenek olarak değerlendirilmiştir. Yabancı pazarların firmalar için taşıdığı en büyük risk ise belirsizliktir. İhracatçı firmalar, bu belirsizliği azaltmak ve yabancı pazarlarda rakipleri karşısında avantaj elde etmek için klâsik pazarlama yeteneklerine ilave farklı bir takım yeteneklere daha ihtiyaç duyarlar. Bu çerçevede, bu çalışmada ihracatçı firmalara yabancı pazarlarda rakipleri karşısında avantaj sağlayan yeteneklerin belirlenmesi amaçlanmıştır. Bu amaçla, Türkiye’de yerleşik 281 imalâtçı-ihracatçı firmanın 300 ihracat girişimi üzerinde gerçekleştirilen araştırma neticesinde, enformasyonel yeteneklerin maliyet ve ürün avantajıyla, ilişki kurma ve pazarlama yeteneklerinin ise maliyet, ürün ve hizmet avantajıyla pozitif yönde ilişkili olduğu tespit edilmiştir.Within the literature, exporting is considered as the simplest strategic option which enables firms to access foreign markets. The greatest risk of foreign markets for firms is uncertainty. In order to decrease this uncertainty and gain advantage against competitors, exporter firms need some additional capabilities which are different from classical marketing capabilities. Within this context, this study aims to define the capabilities which enable exporter firms to gain advantage against competitors in foreign markets. For this aim, an empirical research is conducted with the 300 export venture of 281 Turkish manufacturer-exporters. The results showed that informational capabilities are positively related with cost and product while relationship and marketing capabilities positively related with cost, product and services

The Precision Application of the Long Extension Piece of a Small Straight Piece

DergiPark: 242136trakyafbdIt has been explained for used methots that a small straight piece's extension which is longer of itself is applicated by precision at land and numerical examples (samples) concerned with the subject (topic) has been given.Kısa bir doru parçasınn, kendisinden çok uzun olan uzantısınn hassas olarak aplikasyonu için kullanılan metotlar açıklanmış ye konuyla ilgili sayısal örnekler verilmiştir

The Mediator Roles Of Attitude Toward The Web Site And User Satisfaction On The Effect Of System Quality On Net Benefit: A Structural Equation Model On Web Site Success

The purpose of this study is to examine the mediator roles of attitude toward the web site and user satisfaction on the effect of system quality on net benefit. A new conceptual model for web site success is developed based on previous models in the literature. System quality is one of the most important antecedent of perception of net benefit for customers of B2C sites. The effect of system quality on net benefit has been through user satisfaction in the literature. Some models included attitude toward the web site dimension in the same level with user satisfaction. Therefore, the research model suggested these two variables play mediator roles on the effect of system quality on net benefit. A structural equation model is used to analyze this model. It is statistically proved that attitude toward the web site and user satisfaction play mediator roles on the effect of system quality on net benefit

Yapay sinir ağları ile yatırım değerlemesi analizi

This paper shows that discounted cash flow and net present value, which are traditional investment valuation models, can be combined with artificial neural network model forecasting. The main inputs for the valuation models, such as revenue, costs, capital expenditure, and their growth rates, are heavily related to sector dynamics and macroeconomics. The growth rates of those inputs are related to inflation and exchange rates. Therefore, predicting inflation and exchange rates is a critical issue for the valuation output. In this paper, the Turkish economy’s inflation rate and the exchange rate of USD/TRY are forecast by artificial neural networks and implemented to the discounted cash flow model. Finally, the results are benchmarked with conventional practices.Bu çalışmada geleneksel yatırım değerleme metotlarından olan indirgenmiş nakit akım ve net bugünkü değer modeli ile yapay sinir ağları modelinin tahmin etme özelliğinin birleştirilmesi analiz edilmiştir. Değerleme modellerinin temel bileşenlerinden olan satış gelirleri, maliyetler, yatırım harcamaları ve bunların yıllar içerisindeki büyüme oranları sektörel dinamikler ve makroekonomik faktörlerle yakından ilişkilidir. Bununla birlikte, enflasyon oranı ve döviz kurları bu bileşenlerin değişim oranlarını etkilemektedir. Dolayısıyla enflasyon oranını ve döviz kurlarını tahmin etmek değerlemenin sonucu açısından kritik bir önem taşımaktadır. Bu çalışmada Türkiye enflasyonu ve USD/TRY döviz kuru yapay sinir ağları modeli ile tahmin edilmiş ve bu değişkenler indirgenmiş nakit akım modeli içerisine yerleştirilmiştir. Bu modelin sonuçları geleneksel yöntemler ile karşılaştırılmıştır

Investment Valuation Analysis with Artificial Neural Networks

This paper shows that discounted cash flow and net present value, which are traditional investment valuation models, can be combined with artificial neural network model forecasting. The main inputs for the valuation models, such as revenue, costs, capital expenditure, and their growth rates, are heavily related to sector dynamics and macroeconomics. The growth rates of those inputs are related to inflation and exchange rates. Therefore, predicting inflation and exchange rates is a critical issue for the valuation output. In this paper, the Turkish economy’s inflation rate and the exchange rate of USD/TRY are forecast by artificial neural networks and implemented to the discounted cash flow model. Finally, the results are benchmarked with conventional practices

Antecedents and Consequences of Trust in Public Sector Websites and Social Media

Rapidly developing information and communication technologies have an influence on the whole world and have become an ordinary part of everyday life. Not only people, but businesses and governments are affected by these changes. In this respect, governments use several online media platforms as their own digital face and thus keep pace with the developing technology. Considering the lacks in previous researches, the aim of this paper is to investigate the critical factors influencing the citizens' trust in public sector websites and social media and also the relationship among trust in the public sector, citizen satisfaction and trust in public sector websites and social media. By studying 607 citizens who are users of the website or social media service belonging to the municipalities in Turkey, we found that: (i) perceived quality, perceived usefulness, and facilitation conditions are the factors that affect the citizens' trust in public sector websites and social media, (ii) trust in the public sector websites and social media affects trust in the public sector and, (iii) trust in the public sector affects citizen satisfaction

Investment Valuation Analysis with Artificial Neural Networks

This paper shows that discounted cash flow and net present value, which are traditional investment valuation models, can be combined with artificial neural network model forecasting. The main inputs for the valuation models, such as revenue, costs, capital expenditure, and their growth rates, are heavily related to sector dynamics and macroeconomics. The growth rates of those inputs are related to inflation and exchange rates. Therefore, predicting inflation and exchange rates is a critical issue for the valuation output. In this paper, the Turkish economy’s inflation rate and the exchange rate of USD/TRY are forecast by artificial neural networks and implemented to the discounted cash flow model. Finally, the results are benchmarked with conventional practices

A Different Way of Coronary Lesion Preparation: Stentablation and Rotastenting

Calcified coronary lesions are challenging to deal with, as they require optimal lesion preparation. Direct stenting in this scenario is associated with risk of stent-underexpansion, which is related to in-stent restenosis, target lesion revascularization and stent-thrombosis. We report on the interventional management of an underexpanded bare-metal stent not amenable to high-pressure balloon dilation and cutting-balloon. By using rotablation we could abrade the underexpanded stent struts and the calcification with subsequent implantation of a drug-eluting stent. Follow-up of 6 months revealed good results without evidence of significant restenosis. Our clinical experience and case reports in the literature suggest that this strategy might be an option for underexpanded stents not amenable to conventional techniques

Destek Vektör Regresyon ve İkiz Destek Vektör Regresyon Yöntemi ile Tedarikçi Seçimi

Suppliers’ selection problem has attracted considerable research interest in recent years. Recent literature show that artificial intelligence techniques achieve better performance than traditional statistical methods. Recently, support vector machine has received much more attention from researchers, while studies on supplier selection based on it are few. In this paper, we applied the support vector regression (SVR) and twin support vector regression (TSVR) techniques to predict the supplier credit index. In practice, the suppliers’ samples are very insufficient. SVR and TSVR are adaptive to deal with small samples. The prediction accuracies for SVR and TSVR methods are compared to choose appropriate suppliers. The actual examples illustrate that TSVR methods are superior to SVR.Tedarikçi seçimi sorunu son zamanlarda literatürde oldukça ilgi görmektedir. Güncel literatür, yapay zeka tekniklerinin geleneksel istatistiksel yöntemlerle karşılaştırıldığında daha iyi bir performans sağladığını göstermektedir. Son zamanlarda, destek vektör makinesi, araştırmacılar tarafından çok daha fazla ilgi görse de, buna dayalı tedarikçi seçimi çalışmalarına pek sık rastlanmamaktadır. Bu çalışmada, tedarikçi kredi endeksini tahmin etmek amacıyla, destek vektör regresyon (DVR) ve ikiz destek vektör regresyon (İDVR) teknikleri kullanılmıştır. Pratikte, tedarikçi verisini içeren örneklemler sayıca oldukça yetersizdir. DVR ve İDVR daha küçük örneklemlerle analiz yapmaya uyarlanabilir. Tedarikçilerin belirlenmesinde DVR ve İDVR yöntemlerinin tahmin kesinlikleri karşılaştırılmıştır. Gerçek örnekler İDVR yönteminin DVR yöntemine kıyasla üstün olduğunu göstermektedir