The objective of this study is to examine the impact of renewable and non-renewable energy consumption, income, internet use and urbanization on CO₂ emissions in 38 OECD countries during over the period 1995–2022 using the heterogeneous panel quantile regression technique. The study addresses the existing gap in the literature by analyzing the relationship between income and renewable energy, as well as the Environmental Kuznets Curve (EKC) at specified quantile levels. The findings show that the EKC is more dominant in countries with low CO₂ emissions. Furthermore, the negative relationship between renewable energy consumption and CO2 emissions becomes considerably more significant in quantiles with higher CO2 emissions. The research clearly showed that while urbanisation is an important positive factor in increasing CO2 emissions, the use of the internet as an indicator of digitalization has a decreasing impact on CO2 emissions. Our study provides valuable insights for policymakers to identify effective strategies for renewable energy adoption, digitalization, and urbanization policies to ensure sustainable development while addressing environmental degradation. The results of this study indicate that in order to achieve green economic development, it is essential for governments to prioritize the utilization of renewable energy sources and the advancement of sustainable urbanization practices. Additional robustness checks based on MMQR and SIVQR estimations confirm the reliability of the empirical findings across alternative quantile estimation techniques.

This paper presents total factor productivity (TFP) growth analysis with a panel Stochastic Frontier Approach (SFA) for 26 Türkiye regions from 2004 to 2020. The study is a pioneer in the literature on decomposing TFP growth components at the regional level with the translog production function for the Turkish economy. This work has a fresh approach regarding adjusting the schooling of employment and involving macroeconomic factors in the inefficiency function. The numerous specification tests show considerable production inefficiencies. Therefore, the production frontier is estimated using the True Fixed Effects (TFE) model. The empirical findings reveal that human capital is the primary driver of output growth. Technical efficiency is estimated to be 90.6% on average, with 9.4% of potential output lost due to technical inefficiency. It has been determined that there has been technical progress in labor-saving. Trade has a negative effect on technical efficiency. These findings contribute to understanding TFP change in the Turkish economy with regional data.

Since the contribution of economic sectors to GDP is heterogeneous, they also contribute differently to CO2 emissions and environmental degradation. In this regard, it is crucial to examine the Environmental Kuznets Curve (EKC) hypothesis at the sectoral level. Nevertheless, despite the extensive research conducted on the Environmental Kuznets Curve (EKC) hypothesis, significant gaps remain in the existing literature, particularly at the sectoral level. This study makes a novel contribution to the existing literature on the environmental EKC hypothesis by examining its validity across four distinct sectors: agriculture, industry, manufacturing, and services. Additionally, it makes a second contribution to the literature by examining the effect of energy consumption on CO2 asymmetrically, employing a novel panel non-linear ARDL (PNARDL) method. The study employs annual data from 38 OECD countries, spanning the period from 1990 to 2022. The findings demonstrate that the EKC hypothesis is valid for sectors other than the industrial sector and for the economy as a whole. The turning point of the Kuznets Curve for the total economy is estimated as $29250 GDP per capita. The PNARDL model’s error correction term (ect) is negative and significant. However, the magnitude of the term suggests that the system will return to long-term equilibrium after approximately 2.87 years following any shock. Asymmetric effects are valid for four sectors. Moreover, the empirical results clearly show that energy consumption has asymmetric effects on emissions in both the long and short run. Positive and negative shocks in energy consumption increase CO2 emissions in OECD economies in the long run. It has been determined that agriculture is the sector that causes the most environmental degradation by increasing CO2 emissions. This situation highlights the limited availability of productive capital equipment and renewable sources in the agricultural sector, even in OECD countries. As a result, the findings show that there is a different relationship between each sector’s GDP and CO2 emissions. It is important for policymakers to formulate sector-specific policies to reduce CO2 emissions while fostering GDP growth.

This study examines the drivers of economic complexity for 97 countries over the period 1995 to 2020 by income sub-groups. To investigate determinants of complexity, we develop five novel indexes. Using two-step system GMM (2SGMM) regression with the robust standard errors method, we found that institutional quality, health dimensions and macroeconomic conditions were enormously significant economic complexity drivers. However, the findings vary according to the country groups with different income levels. While the importance of openness and health dimensions are prominent in low and middle-income countries, capital stock and openness are the principal elements in the high-income group. The institutional quality is statistically significant and considerably affects on complexity in each group and across the panel. The education dimension of human capital has a positive effect only in the high-income group and across the panel, while it is negative in the middle and low-income groups, but its effect is weak. Moreover, these findings are valid in the long run. From a policy perspective, the findings suggest that macroeconomic policies focused on institutional quality, openness and healthcare as critical components of economic complexity should be crucial goals, especially for low and middle-income countries. JEL Classification: O11, O43, I15, I25.

Purpose This article investigates the validity of the different types (conditional, unconditional, deterministic, stochastic) of ß-convergence in per capita GDP for EU-28 and EU-19 between 1990 and 2019. Design/methodology/approach The study uses nonstationary heterogeneous panel-data methodology. Findings The panel data reveal that both conditional and unconditional ß-convergence are valid in EU-28 countries However, only conditional convergence exists in EU-19 countries; group-specific findings show that the income levels of 10-EU countries converge toward the EU-19 average and 11-EU countries converge to the EU-28. The convergence speed to EU average varies between 15 and 18%. The robustness of the augmented mean group (AMG) findings are checked with common correlated effects mean group (CCEMG) and are consistent. Moreover, panel unit root tests are applied to examine the stochastic and deterministic convergence of the average EU per capita income in the two groups of EU economies. The findings show no evidence of deterministic or stochastic convergence in EU countries. Besides, conditional convergence has not been experienced in countries such as Bulgaria, Croatia, Czech Republic, Hungary, Latvia, Malta, Romania, Slovakia and Slovenia, which are new members of the EU. As a remarkable aspect of the study, the evidence suggests that the Brexit is economically rational for the UK. Originality/value The growth and convergence processes of economies differ from each other. Convergence studies in the literature are generally based on the cross-section OLS methodology. In this context, the study is one of the rare studies to examine convergence using heterogeneous panel techniques and allows the convergence of countries to the EU average to be analyzed individually.

This study examines the asymmetric effect of economic complexity and macroeconomic stability on carbon emissions for OECD countries over the period between 1995 and 2020. We construct a nonlinear panel ARDL-PMG model to assess the short- and long-run impact of the positive and negative shifts of economic complexity and macroeconomic stability on carbon emissions. The asymmetric findings prove that macroeconomic stability and instability positively impact carbon emissions in the long run. Moreover, asymmetric economic complexity shocks increase pollution in the long run. The impact of short-run shocks on carbon emissions returns to long-run equilibrium in 2.75 years (33 months) with an annual correction of 36.4%. One of the most striking findings of this study is that the sophisticated, complex production structure may pollute the environment less than traditional production. However, it still increases environmental degradation in absolute terms. Therefore, economic complexity only slows the rate of increase in environmental pollution. Capital stock and institutional quality have a weaker effect on emissions, while openness does not.

The level of economic income, population density and sources of energy supply is critical in assessing environmental quality. Recent empirical studies paid limited attention to the role of renewable (RE) and fossil energy (NRE) supply in carbon pollution regarding the Environmental Kuznets Hypothesis (EKC). Therefore, this study investigates the asymmetric relationships between carbon emissions and energy sources on the one hand and the environmental Kuznets hypothesis on the other hand for OECD countries, comprising countries with significant renewable energy supplies. The study includes the annual data from 1990 to 2021 and performs panel non-linear ARDL regression. The empirical results clearly show that RE and NRE have asymmetric effects on emissions in the long run but not in the short run. Both positive and negative shocks in RE reduce CO2 emissions in OECD economies, while asymmetric shocks in NRE substantially increase them. Increasing RE supply is clearly effective in reducing emissions. However, unlike most previous studies, this study shows that RE does not significantly reduce CO2 emissions in OECD countries. The error correction term (ect.) in the NARDL model is negative and significant. The magnitude of the term indicates that the system will return to long-term equilibrium about 4.2 years after any shock. Furthermore, we show that the EKC Hypothesis is supported in OECD countries. The turning point of the EKC is at $4085.77 per capita. Besides, regression with Driscoll-Kraay standard errors and Augmented Mean Group (AMG) estimator approach were used for robustness checks. The findings from the robustness check are consistent with the NARDL findings. Policies based on the promotion of a low-carbon and sustainable green environment should place greater emphasis on renewable resources even in OECD countries. Moreover, while many studies in the literature address asymmetric effects and EKC as energy consumption or utilisation, the novelty of this study is that it approaches the issue regarding energy supply with asymmetric effects for RE and NRE.

Concentration on exports is important in terms of the contribution of exports to sustainable economic growth and income level. Therefore, literature researching the relationship between export concentration and income has emerged. However, the relationship in question has not yet been extensively analyzed concerning high-technology exports. The current study investigates the product concentration/diversification at the high-technology level, which has made it a pioneering study and the validity of the resource curse hypothesis for the high-technology sector. The findings obtained by panel data econometrics in a sample from 1988 to 2017 in 49 countries show that the U-shaped relationship put forward for general exports does not apply to high-technology (HT) exports. There is no diversification curve between HT-export concentration and income. However, the driver of diversification in HT exports has been found to be income level. As income levels increase, countries can diversify HT products. Besides, natural resource wealth is not a hindrance to the diversification of HT exports; instead it contributes to diversification. This finding suggests that resource abundance does not exclude technological progress and knowledge economy activities. As control variables, country scale and trade volume indicators contribute positively to HT concentration. This result contradicts the literature put forward on general export.

İhracatta yoğunlaşma, ihracatın gelir ve büyümeye verdiği katkı ve bu durumun sürdürülebilirliği açısından önemlidir

Teknolojinin ulusal düzeyde ortaya çıkması ve uluslararası yayılım göstermesi sadece mühendislik ve uygulamalı disiplinler tarafından değil aynı zamanda iktisadi koşullar tarafından belirlenen bir olgudur. Teknoloji yoğun ihracatın iktisadi faktörlerini araştıran mevcut ampirik literatürde farklı bulgu ve kanıtlar sunulmaktadır. Bu çalışma, sofistike ve teknoloji yoğun ihracatın (HT) makro iktisadi belirleyicilerini tespit etmeye yönelik literatürde bulunan aktif bir tartışmaya ağırlıklı olarak orta ve yüksek gelir grubundaki ülkeler örnekleminde katkı sunmaktadır. İhracat sofistikasyon düzeyi HT payı yanı sıra EXPY endeksiyle hesaplanmıştır. Analiz panel veri ekonometrisi yöntemleriyle 1988-2017 dönemi ve 49 ülke için gerçekleştirilmiştir. Açıklayıcı değişkenler olarak fiziki-beşeri sermaye, Ar-Ge, doğrudan yabancı yatırımlar, döviz kuru ve ülke ölçeği seçilmiştir. Ekonometrik bulgular, yerel teknolojik kapasiteyi oluşturan fiziki sermaye, beşeri sermaye ve Ar-Ge harcamalarının HT ihracatının baskın kaynakları olduğunu göstermektedir. HT ihracatı artışında ulusal teknolojik kapasiteyle birlikte yayılım ve ölçek etkileri de önemlidir. Beşerî sermaye önemli bir düzeyde ve üstelik diğer bütün değişkenlerin hepsinden daha fazla HT ihracatını artırmaktadır. Doğrudan yabancı yatırımların yayılım etkisi anlamlıdır ancak etkinin boyutu ulusal teknolojik kapasiteyi oluşturan değişkenlerin boyutundan daha düşüktür. Sonuçlar, kamu politikalarının eğitim, yatırım ve Ar-Ge alanlarındaki kompozisyonun önemine işaret etmektedir.

This study examines the relationship between renewable energy consumption and economic growth in Brazil, China, and India using cointegration analysis and causality testing for the period 1971–2014. In this regard, we use autoregressive distributed lag (ARDL) bounds test approach and use the causality approach of Hatemi-J (2012) which is taking into account asymmetric behavior in causality. The ARDL findings show (i) when we look at the long-run coefficients obtained from the estimates, renewable energy consumption has a positive effect on growth in Brazil and China. However, the coefficient of renewable energy in India is not statistically significant. Additionally, the impact of gross fixed capital and total employment on economic growth is positive in all countries. In this context, we can say that the contribution of gross fixed capital investment and total employment to economic growth in all countries is more than the contribution of renewable energy consumption; (ii) the short-run forecast findings, we can state that renewable energy consumption has a positive effect on economic growth in Brazil. At the same time, one period-lag renewable energy consumption has a positive impact on economic growth in China. In India, renewable energy consumption has no statistically significant effect on economic growth. On the other hand, while capital has a positive effect on economic growth in all countries, total employment has a positive effect only on economic growth in Brazil and China; and the asymmetric causality findings show (iii) there is no causal relationship between renewable energy consumption and economic growth in all countries in both positive shocks and negative shocks.

This study aims to empirically test the Armey Curve hypothesis (optimal government size) for Turkey with panel data consisting of 81 provinces and 17 years. In this context, a quadratic model has been established in which economic growth is the dependent variable, and public expenditures are the independent variable. AMG estimates obtain the optimal size of public expenditures. The results indicate that the optimal level of public expenditures is 25.2%. Moreover, province-specific findings provide that the Armey curve is valid in 16 provinces, and the critical point of the curve takes values ranging from 12%(Istanbul) to 46%(Elazig). Considering the average volume of public expenditures is 31.6% throughout the panel, it is concluded that the expenditures exceed the optimal level. These results show that public expenditures are in the region of diminishing returns. Therefore, in order to maximize the growth rate, public expenditures should be reduced to an optimal level.

This study aims to present new findings to the literature by analyzing the impact of high-tech(HT) exports on revenue using panel data methods in 49 countries and under both Cobb-Douglas and Translog production functions for the period 1988-2017. No other study has been found in the literature investigating the HT-Income relationship in the Translog production function. In this aspect, the current analysis is a pioneer study. Regression coefficients were estimated by the Driscoll-Kraay method, which produces robust standard errors in cases where OLS assumptions cannot be met. Furthermore, the existence of cointegration between the series was investigated by the stationarity of the residuals. According to the findings, the income elasticity of the physical capital contributing to the scale is 0.668; income elasticity of human capital was calculated as 0.584 and income elasticity of HT exports was calculated as 0.071. However, HT exports have been found to contribute to income per labor force, while human capital contributes to income per labor force along an increasing curve. The relationship between physical capital and income seems decidedly linear. These findings were tested for robustness with alternative regression methods in addition to the main models, and results compatible with the existing models were obtained.

Bu çalışmanın amacı, yüksek teknoloji(HT) ihracatın gelir üzerindeki etkisini panel veri yöntemleriyle 49 ülke ve 1988-2017 dönemi için hem Cobb-Dougles hem de Translog üretim fonksiyonu altında analiz ederek literatüre yeni bulgular sunmaktır. Translog üretim fonksiyonunda HT-Gelir ilişkisini araştıran başka bir çalışmaya rastlanılmamıştır. Bu yönüyle mevcut analiz öncül bir çalışma özelliği taşımaktadır. Referans modelde SEK varsayımlarının karşılanamaması nedeniyle söz konusu problemlerin varlığında dirençli standart hatalar üreten Driscoll-Kraay yöntemiyle regresyon katsayıları tahmin edilmiştir. Ayrıca, seriler arasında eşbütünleşmenin varlığı artıkların durağanlığı ile araştırılmıştır. Elde edilen bulgulara göre, fiziki sermayenin ölçeğe katkısı olan gelir esnekliği 0,668; beşeri sermayenin gelir esnekliği 0,584 ve HT ihracatının gelir esnekliği 0,071 düzeyinde hesaplanmıştır. Bununla birlikte, HT ihracatının işgücü başına gelire azalarak artan, beşeri sermayenin ise işgücü başına gelire ise artarak artan bir eğri boyunca katkı verdiği tespit edilmiştir. Fiziki sermaye ve gelir ilişkisinin ise doğrusal olduğu görülmektedir. Bu bulgular ana modellere ek olarak alternatif regresyon yöntemleriyle sağlamlık kontrolünden geçirilmiş ve mevcut modellerle uyumlu neticeler elde edilmiştir.

The human development index was designed in 1990 to evaluate countries' development levels within the framework of UNDP. Following this, a series of indices were developed to analyze the different dimensions of human development While these indices make intercountry comparisons, they do not allow evaluation at a local level. However, determining human development at the local level has great importance. For this purpose, using UNDP methodology, four different indices were calculated at the province level covering the period between 2009 and 2018. In this respect, a comprehensive data set is presented to the literature. The results show that, although provinces have progressed in all aspects of human development, they have not yet been able to reach a very high human development category. The primary factor restraining human development levels is found to be low degrees of education in the provinces. Although regional and gender inequalities both in education and in income distribution have decreased, they are nonetheless still quite high. The most developed provinces by the HDI index are Ankara, Istanbul, and Kocaeli, whereas the lowest provinces are Van, Sanliurfa, and Agri. By the inequality-adjusted HDI no province has as yet reached a very high human development level. While the minimum loss due to inequality was seen in Muglathe province, the highest loss is in Hakkari.

Birlesmis Milletler Kalkinma Programi cercevesinde ulkelerin kalkinmislik duzeyini degerlendirmek amaciyla 1990 yilinda insani gelisme endeksi olusturulmustur. Sonraki yillarda ise insani gelismenin degisik boyutlarini analiz eden farkli endeksler gelistirilmistir. Soz konusu endeksler ulkelerarasinda bir karsilastirma yapmakta iken yerel duzeyde degerlendirmeye imkân vermemektedir. Diger yandan, Turkiye ozelinde illerin insani gelisme durumlarinin her yonuyle tespit edilmesi buyuk onem arz etmektedir. Bu amacla calismada, UNDP metodolojisini kullanarak, 81 il duzeyi ve 2009-2018 donemini kapsayan bir surec icin dort farkli endeks olusturulmustur. Bu yonuyle, literature genis ve ozgun bir veri seti sunulmaktadir. Sonuclar incelendiginde, insani gelismenin her alaninda illerin ilerleme gosterdigi ancak cok yuksek insani gelisme kategorisine ulasilamadigi gorulmektedir. Insani gelisme degerlerini baskilayan temel etken ise illerin dusuk egitim duzeyleri olarak karsimiza cikmaktadir. Egitim ve gelir dagilimi alanlarinda bolgesel esitsizlikler ve cinsiyet esitsizlikleri, azalmasina ragmen hala oldukca yuksek seviyelerdedir. HDI endeksinde en gelismis iller Ankara, Istanbul ve Kocaeli; en alt siradaki iller ise Van, Şanliurfa ve Agri olarak tespit edilmistir. Esitsizlik uyarlanmis HDI endeksinde ise hicbir ilimiz cok yuksek insani gelisme duzeyine ulasamamaktadir. Esitsizlik kaybinin en az oldugu il Mugla iken en cok oldugu il ise Hakkari’dir.

Çalışmada nitelik uyarlanmış beşeri sermayenin işgücü başına düşen gelir düzeyi üzerindeki etkileri uzun dönemde analiz edilmektedir. Kullanılan yöntem yatay kesit bağımlılığı ve heterojenlik koşullarını dikkate alan CCEMG ve AMG tahmincileridir. Çalışma 80 ülkeyi ve 1976-2013 dönemini kapsamaktadır. Sağlıklı sonuçlar alabilmek için petrol zengini ülkeler veri setine dahil edilmemiştir. Her iki yöntemden elde edilen katsayılara göre uzun dönemde nitelik uyarlanmış beşeri sermaye işgücü başına düşen gelir üzerinde pozitif ve anlamlı bir etkiye sahiptir. Karşılaştırmalı sonuçlara göre nitelik uyarlaması yapılmadan beşeri sermayenin gelir üzerindeki etkisini ölçmeye çalışmak, değişkenin gerçek etki gücünden abartılı değerler elde edilmesine yol açmaktadır.

The current research is an empirical investigation of the long-run and causal relation between energy consumption and export sophistication. It employs the panel cointegration analysis and cointegration regression using FMOLS and DOLS, for 31 OECD countries covering time span 1990–2016. The results show that there is strong bi-directional causality between variables. The energy consumption elasticities of high technology exports are comparatively high than medium and low tech export. The magnitude of the elasticity demonstrates that a 1% boost in energy consumption is expected to result in 0.81% growth in high technology export share. Moreover, any boost in a share of real investment is expected to have a powerful impact on high and medium tech export growth. It states that energy investment policies are expected to spur share of high technology exports in OECD countries. This paper is a pioneering study to investigated the relationship between energy consumption and export at the technology level.

İktisat literatüründe işsizliğin uzun dönem eğilimlerini açıklayan iki önemli görüş bulunmaktadır. Bunlardan ilki “doğal oran hipotezi” diğeri ise “histeri hipotezi” olarak bilinmektedir. Doğal oran hipotezine göre uzun dönemde işsizlik, doğal oranına ulaşacak ve bu oran üzerinde enflasyon ile işsizlik arasındaki değiş-tokuş ilişkisi sona erecektir. Kısa dönemde ise söz konusu değiş tokuş ilişkisi geçerli olacaktır. Histeri hipotezi yaklaşımı ise şokların işgücü piyasasındaki katılıklar nedeniyle işsizlik düzeyi üzerinde kalıcı etkilere sahip olduğunu ileri sürmektedir. İktisadi bir şoktan sonra işsizlik oranı eski seviyesinin çok üzerinde bir patikaya oturacaktır. Bu görüşe göre uzun süre yüksek işsizlik yaşanması doğal işsizlik oranının eski seviyesine dönmesine engel olacaktır. Bu çalışmada OECD ve Türkiye ekonomisi için 1980-2016 yılları arasında işsizlik oranına karşılık gelen enflasyon oranları arasındaki doğrusal ilişkiden hareketle doğal işsizlik oranı ekonometrik olarak hesaplanmaya çalışılmıştır. Elde edilen katsayılar istatiksel olarak anlamlı ve iktisat teorisiyle uyumlu işaretlere sahiptir. Söz konusu dönemde Türkiye ekonomisi için doğal işsizlik oranı %9.14 seviyesinde hesaplanmıştır. OECD ülkeleri için ise İşsizlik oranı %1 puan artığında enflasyon oranı söz konusu dönem için ortalama olarak %0.9 puan azalmıştır. Doğal işsizlik oranı ise OECD ülkeleri için %6.12 olarak hesaplanmıştır. Bu sonuçlar aynı zamanda söz konusu ülkeler için enflasyon ile işsizlik arasındaki ödünleşmeyi gösteren Philips Eğrisi’ nin katsayılarını göstermektedir.

There are two important views in the economics literature that explain the long-term trends of unemployment. The first one is known as "natural rate hypothesis” and the other one is known as "Hysteresis Hypothesis". According to natural rate hypothesis, long-term unemployment will reach its natural rate, and the trade-off between inflation and unemployment will end up on this rate. In the short term, that trade-off relationship will be valid. The hysteresis hypothesis approach claims that shocks have lasting effects on the level of unemployment due to rigidities in the labor market. The unemployement rate will go up to a very high level above the old level after an aconomic shock. According to this opinion, being of long term unemployement will prevent the natural rate of unemployment from returning to its former level. In this study, is aimed to calculate natural rate of unemployment econometric based on the linear relationship between inflation rates corresponding to the unemployment rate for OECD and Turkey between 1980-2016. The finding coefficients are significant statistically and have signs compatible with the theory of economics. In this period natural rate of unemployment for Turkey's economy was calculated 9.14%. For the OECD countries, the unemployment rate increased by 1 percentage point and the inflation rate decreased by 0.9 percentage points on average for the mentioned period. The natural rate of unemployment was calculated as 6.12% for OECD countries. These results are also showing Philips Curve coefficients as tradeoff between inflation and unemployment for Turkey and OECD.