This paper uses high-frequency spot price data from fourteen wholesale electricity markets in Europe to analyze asymmetric volatility in European day-ahead power markets with Exponential GARCH (E-GARCH) and TARCH models. Our data set ranges from 1992 to 2015 and consists of approximately 926,000 observations. As such, this paper constitutes the most extensive and comprehensive work conducted so far on European power markets, to the best of our knowledge. Unlike most of the literature that treats price as a continuous variable and attempts to model its trajectory, this paper adopts a unique approach and regards each hour in a day a separate market. The results show, in post-2008 period, the most expensive electricity is consumed in Turkey, Ireland, and UK while the cheapest power is in Russia, Nordic countries, and Czech Republic. Russia, Poland, and Czech Republic have the least volatile markets while France, Ireland, and Portugal have the most volatile ones. Volatility has decreased in many European countries in post-2008 period. Besides, we find magnitude effect is usually larger than the leverage effect, meaning that the absolute value of price change is relatively more important than the sign of the change (whether it is an increase or a decrease) to explain volatility in European day-ahead power markets. Moreover, the results imply there is not a uniform inverse leverage effect in electricity prices; that is, price increases are more destabilizing in some European markets (e.g. Poland, Slovenia, Ireland, Netherlands) than comparable price decreases but vice versa also holds true in some other countries (e.g. Portugal and France). Leverage (or inverse leverage) effect in post-2008 period is relatively stronger in Portugal, France, and Ireland, but its impact is quite limited in Turkey and Germany. Furthermore, although the impact of seasonality on prices is obvious, a specific pattern cannot be identified. Finally, large changes in the volatility will affect future volatilities for a relatively longer period of time in Nordic countries, Ireland, and the UK while changes in current volatility will have less effect on future volatilities in Czech Republic, Russia, and Turkey.

Energy Economics, 56(4), 398-409,

More than half of the countries in the world have introduced a reform process in their power sectors since 1980s. Adapting a political economy perspective, this paper attempts to discover the impact of political economic variables on the liberalization process in electricity markets. Empirical models are developed using panel data from 55 developed and developing countries covering the period 1975–2010. The research findings clearly show that political variables have a significant impact on the reform progress. Consistent with public choice theory and economic theory of regulation, our results suggest that a portion of the differences in the reform experiences of reforming countries in the past three decades can be explained by differences in the relative strength of interest groups. We find that industry sector has a significant impact on the pace of power market liberalization process; and as its size gets larger, so does its influence. Our results also imply that countries receiving foreign financial support are more likely to liberalize their electricity markets, which underlines the point that reforms may not be always voluntary. In addition, our findings suggest that government ideology is one of the determinants of the progress in electricity market reform process. Finally, the paper also questions whether politicians’ education and profession matter for the electricity market reforms. Overall, the results show they do.

The Energy Journal, 35(3), 91-128,
The paper explores whether the question of why some countries are able to implement more extensive reforms is closely related to the question of why some countries have better institutions than others. We analyze this question by using an empirical econometric model based on Poisson regression with cross-section data covering 51 states in the US, 13 provinces in Canada and 51 other countries. In the course of the study, we check the validity of three important arguments of New Institutional Economics (NIE) for the power market liberalization process. The first argument is the “path-dependency”. To test its impact on the reform progress, we try to explain whether the background of the chairperson of the regulatory agency when reforms started or that of the governor/minister responsible for energy policy at that time has an impact on the subsequent reform progress. The second argument is the impact of “democracy” as an institution on the reform progress. We look at the effect of two important indicators of democracy (i.e., civil liberties and political rights) on the reform progress. The final argument of NIE is about transaction costs. We concentrate on the level of corruption in a country as one of the key factors that determine transaction costs and try to explore its impact on the reforms. The results show that the backgrounds of the chairperson and the minister/governor, the level of democracy and corruption in a country are significantly correlated with how far reforms have gone in that country. The negative relationship between reform progress and civil liberties may indicate that reforms may be limited in democratic countries with strong civil society institutions such as trade unions or other organized structures in the society that may consider reforms as ‘harmful’ to their self-interest.

Energy Economics, 39(5), 239-251,
One of the main expectations from power market reform has been a reduction in both price-cost margins and cross-subsidy levels between industrial and residential consumers. This paper focuses on this issue by looking at the impact of the electricity industry reforms on residential and industrial electricity price-cost margins and their effect on cross-subsidy levels between consumer groups. Using panel data for 63 developed and developing countries covering the period 1982–2009, empirical models are developed and analyzed. The research findings suggest that there is no uniform pattern for the impact of reform process as a whole on price-cost margins and cross-subsidy levels. Each individual reform step has different impact on price-cost margins and cross-subsidy levels for each consumer and country group. Our findings imply that reform steps have different impacts in different countries, which supports the idea reform prescription for a specific country cannot easily and successfully be transferred to another one. So, transferring the formal and economic structure of a successful power market in a developed country to developing countries is not a sufficient condition for good economic performance of the electricity industries in developing countries. Furthermore, the study suggests that power consumption, income level and country-specific features constitute other important determinants of electricity price-cost margins and cross-subsidy levels.

Energy Policy, 39(3), 1080-1092,
The last two decades have witnessed widespread power market reforms in both developed and developing countries that have cost billions of dollars. Among the key aims (and assumptions) of these reforms, there has always been realization of improvements in power sector efficiency. This paper questions the validity of this hypothesis. Using panel data from 92 countries covering the period 1982–2008, empirical models are developed and analyzed. The research findings suggest that the impact of the reforms on electricity industry performance is statistically significant but also limited. The results imply that, after controlling for country-specific variables, application of liberal market models in electricity industries slightly increases efficiency in power sector. Besides, we detect a positive relationship between reform process and the percentage share of network (transmission and distribution) losses in total electricity supplied, meaning that as countries take more reform steps the network losses as a fraction of power generated tend to increase. Moreover, the study puts forward that income level and other country specific features are more important determinants of industry efficiency than the reform process. Overall, contrary to expectations of substantial increases in sector efficiency, the paper concludes that introducing a decentralized market model with competition in the electricity sector has a limited increasing effect on power industry performance.

Energy Policy, 39(10), 6551-6560,
The last three decades have witnessed many electricity industry reform processes in more than half of the countries in the world. The reforms have aimed, inter alia, at encouraging private investments in electricity infrastructure, enhancing security of electricity supply and making power industry operate in line with the requirements of the sustainable development. Using an original panel dataset from 55 developed and developing countries covering the period from 1975 to 2010, this study aims at finding out to what extent these objectives have been materialized so far. Econometric models are used to identify the effects of electricity market liberalization on these variables. The research findings suggest that the progress toward the electricity market reform is associated with a decline in private investments in the electricity industries of developing countries, higher levels of self-sufficiency in electricity supply and lower CO2 emissions from electricity generation.

Renewable and Sustainable Energy Reviews, 31(3), 1-8,
In the early 2000s, the Republic of Turkey has initiated an ambitious reform program in her electricity market, which requires privatization, liberalization as well as a radical restructuring. The most controversial reason behind, or justification for, recent reforms has been the rapid electricity demand growth; that is to say, the whole reform process has been a part of the endeavors to avoid the so-called “energy crisis”. Using cointegration analysis and autoregressive integrated moving average (ARIMA) modelling, the present article focuses on this issue by both providing an electricity demand estimation and forecast, and comparing the results with official projections. The study concludes, first, that consumers’ respond to price and income changes is quite limited and therefore there is a need for economic regulation in Turkish electricity market; and second, that the current official electricity demand projections highly overestimate the electricity demand, which may endanger the development of both a coherent energy policy in general and a healthy electricity market in particular.

Energy Policy, 35(2), 1129-1146,
On average, energy demand of Turkey is mounting by 8% annually, one of the highest rates in the world. Among primary energy sources, natural gas is the fastest growing one in Turkey. Gas consumption started at 0.5 bcm (billion cubic meters) in 1987 and reached approximately 35 bcm in 2007. Turkish natural gas usage is projected to further increase remarkably in coming years. The present paper focuses the characteristics of this demand and estimates short and long-run price and income elasticities of sectoral natural gas demand in Turkey. The future growth in this demand is also forecasted using an ARIMA modelling and the results are compared with official projections. The paper reveals that natural gas demand elasticities are quite low, meaning that consumers do not respond possible abusive price increases by decreasing their demand or substituting natural gas with other energy sources. Since consumers are prone to monopoly abuse by incumbent, there is a need for market regulation in Turkish natural gas market. Based on forecasts obtained, it is clear that the current official projections do not over/under-estimate natural gas demand although past official projections highly overestimated it.

Applied Energy, 87(1), 211-219,
Since the early 1980s, electricity industry reforms have been initiated in more than half of the countries in the world. Among the primary targets of these reform schemes, there has been an increase in efficiency of the sector; and it is implicitly assumed that government support to energy technology R&D will progress in line with the reform process as the former is required to sustain improved efficiency in the middle and long run. The paper reviews the relation between reform process in electricity markets and government support to energy R&D. Using panel data from 27 countries covering the period from 1974 to 2008, this study aims at finding out to what extent the expected correlation between reform process and government support to energy R&D has in practice been materialized so far. The findings suggest that, contrary to expectations, the progress toward electricity market reform is associated with reduced government support to a variety of energy R&D activities, which threatens sustainable efficiency improvements in the power industry.

Renewable and Sustainable Energy Reviews, 17(1), 110-118,
The world׳s most expensive motor fuel (gasoline, diesel and LPG) is sold most likely in the Republic of Turkey. This paper investigates the key issues related to the motor fuel prices in Turkey. First of all, the paper analyses the main reason behind high prices, namely motor fuel taxes in Turkey. Then, it estimates the elasticity of motor fuel demand in Turkey using an econometric analysis. The findings indicate that motor fuel demand in Turkey is quite inelastic and, therefore, not responsive to price increases caused by an increase in either pre-tax prices or taxes. Therefore, fuel market in Turkey is open to opportunistic behavior by firms (through excessive profits) and the government (through excessive taxes). Besides, the paper focuses on the impact of high motor fuel prices on road transport associated activities, including the pattern of passenger transportation, motorization rate, fuel use, total kilometers traveled and CO2 emissions from road transportation. The impact of motor fuel prices on income distribution in Turkey and Turkish public opinion about high motor fuel prices are also among the subjects investigated in the course of the study.

Energy Policy, 69(6), 143-153,
The attitude towards ICT determines the amount of incentive for practicing with it, which may directly affect ICT literacy. So, students’ attitude inter alia is one of the substantial building blocks of ICT literacy, which in turn is an important component of improved student achievement brought about by it. This paper is devoted to exploring the determinants of students’ attitudes towards ICT. On recognizing the complexity of integration of ICT into education systems and unlike previous research that has largely focused on the idea that student’s learning engagement can be boosted through the availability and use of ICT alone, this paper acknowledges that integrating ICT into education is a complex process and the link between supplying ICT resources and enhanced student attainment is far from straightforward. Using rich PISA 2018 survey data from N = 129,724 students in 47 countries/economies, the results from this paper indicate that girls have better attitudes towards ICT than boys; students in private schools have more interest in ICT than those in public ones; students using ICT outside of school for leisure have a higher level of interest; and students with higher levels of fear of failure are more interested in ICT.

Interactive Learning Environments,
This paper utilizes OECD’s original PISA 2012 dataset to investigate the impact of access to ICT, student background and school/home environment on academic performance of students. Using cross-section data from 4848 15-year-old students in Turkey, ordered logit models are developed and analyzed. The results indicate that (i) availability of internet connection at home or school and student’s possession of his/her own room at home have positive impacts on academic success, (ii) internet connection at schools may not be used for school-related activities and therefore distracts student’s attention from schoolwork, (iii) as student-per-teacher ratio or school size increases, the academic success of students declines, (iv) pre-primary education and education in student’s native language contribute to academic achievement, (v) there is a positive relationship between education level of parents and student’s performance at school. Using additional data from 22,273 students, the paper also presents an international analysis that compares the results from Turkey with those from Germany, France and the United Kingdom. Finally, the urgent need for collection of micro level (at student, school or parent level) data on Turkish education system is underlined.

Computers & Education, 82(2), 26-49,