developed countries

 Carbon tax is one of the most important policy tools in the field of energy, which is applied to the consumption, production or distribution of fossil energy, including oil products, coal, natural gas, etc. The purpose of carbon tax is to reduce economic and environmental effects caused by pollution by including environmental costs in the price of goods and services. This policy tool can bring positive economic and environmental consequences through changes in consumer and producer behavior. The purpose of this study is to investigate the effects of carbon tax on energy-intensive and non-energy-intensive industries in different regions of the world.

Since a CGE model can describe the interactions between different factors in macroeconomic systems and examine the effects of a policy at the global level, therefore, a dynamic multi-regional CGE model has been used to better understand the policy effects.

The results show that the carbon tax in all scenarios leads to an increase in the price of goods with high energy intensity in all regions, and the price of goods with low energy intensity decreases, except in the group of developed and high-income countries. Production in the energy-intensive and non-energy-intensive sectors is facing an average decrease. Imports in the energy-intensive sector, except for the group of countries with higher-than-average income, will decrease for other groups, and in the non-energy-intensive sector as well.

To investigate the effect of carbon tax on the industries of different countries, first the countries of the world were grouped into 5 regions based on the criteria of the World Bank and then 5 policy scenarios based on the report of the International Energy Agency were implemented in each region. For modeling, a dynamic calculable general equilibrium model was used in order to achieve more accurate results, and then important industrial consequences were obtained by solving the model. From the results of this research and the studies that have been carried out so far, it can be seen that what is decisive in the consequences of the implementation of the carbon tax is the region and the country implementing the policy. Based on this, the policy makers, considering the national and regional conditions and being aware of the possible effects of the policy, can include assumptions in the design and implementation of the policy in order to achieve efficient and appropriate conditions in the implementation of the carbon tax by reducing the negative effects. Based on the results of the research, it was observed that due to the differences in the regions, the macroeconomic effects in the industry will be different for different regions of the world. Therefore, one of the important points in the effort to bring the emission of greenhouse gases to zero is to pay attention to the differences in industries in different countries and the coordinated actions of the governments with each other for technical and financial support in order to accelerate the transformation of clean energy and reach the commitment goal. Since energy consumption is mainly related to production activities, especially production from energy-intensive industries, reducing greenhouse gas emissions from industry takes more time than some economic sectors. For this purpose, governments should present regular and specific programs to attract investments in the long term so that they can guide industries in the direction of deploying the most efficient technologies. The governments that implement carbon tax policies can also use the collected tax revenues to strengthen energy innovation. Therefore, industries that use unclean energy sources as production inputs, by upgrading production technologies, in addition to reducing production costs, can specialize in producing clean products

Studding the entrepreneurship literature shows that the Economic performance and the extent of entrepreneurial activities depend on the quality and different levels of institutions, and in addition, the mechanism of institutions' influence on entrepreneurial activities in developed and developing countries differs. The purpose of this research is to understand the difference in the type of influence of micro and macro institutions on entrepreneurial activities in developed and developing countries. For this purpose, while using the dynamic panel data, the good governance index and the business environment index used as macro and micro institutional factors, respectively. The results showed that the good governance significantly increase the level of entrepreneurial activities in both developing and developed countries. Contrary to expectations, micro-institutional factors do not increase the level of entrepreneurial activities in the studied developing and developed countries. The degree of economic freedom has a small effect on entrepreneurial activities in developed countries, while it strengthens entrepreneurship in developing countries. Government expenditure has a positive impact  on the level of entrepreneurial activities in developing countries, but it is ineffective in developed countries. Economic growth in both groups of countries has positive impact on the level of entrepreneurial activities. The impact of liquidity on the entrepreneurial activities of developing and developed countries is negative and positive, respectively.

In an era of economic complexity, where goods and services are produced using advanced technologies and with significant diversity, achieving economic growth without environmental pollution has become one of the primary goals for nations worldwide. This objective necessitates measures such as investment in knowledge-based production, which in turn relies heavily on investment in research and development.  The present study aimed to examine the relationship between multidimensional economic complexity and inclusive green economic growth. Given the geographic proximity of some developed and developing countries, the research employed a spatial panel econometric method using data from these nations. The results indicated a significant relationship between inclusive green growth and economic complexity in both developed and developing countries. However, this relationship is relatively weaker in developing countries.

The present study examines the impact of shadow banking on inflation rates in four groups of selected countries (including developed countries with high levels of shadow banking, developed countries with low levels of shadow banking, developing countries with high levels of shadow banking, and developing countries with low levels of shadow banking) during the period 2002-2020. The research modeling is based on dynamic panel patterns, and the relationships between variables are estimated using the Generalized Method of Moments (GMM) technique. The results of the model estimation in two groups of countries under study, namely developed countries with high levels of shadow banking and developing countries with low levels of shadow banking, indicate that the expansion of shadow banking leads to increased inflation, with this effect being exacerbated through the production channel. Conversely, the findings suggest a negative impact of shadow banking on inflation in developed countries with low levels of shadow banking and developing countries with high levels of shadow banking. It is worth noting that the results of the model estimations show that in none of the four groups of countries examined, shadow banking has led to inflation through the money creation channel. It is worth noting that the results of the model estimations show that in none of the four groups of countries examined, shadow banking has led to inflation through the money creation channel.

Economic complexity is an index that has been raised in the last decade and indicates the use of technology in the process of producing goods and services of a country, which leads to increased economic growth and prosperity by creating a productive structure in the composition, increased productivity and diversity of manufactured products. Economic complexity is expected to affect energy consumption because the type of products produced is an important determinant of energy consumption. If countries operate in energy-intensive industries such as metals, chemicals, and forest products, energy consumption will be high, and if they specialize in low energy and highly complex products, energy consumption in these countries will decrease. In addition, the level of technological knowledge of countries can significantly affect energy efficiency. Therefore, in this research, the effects of economic complexity and economic growth on renewable, non-renewable and total energy consumption in developing and developed countries in the period of 2000-2020 have been investigated by GMM method.

GMM estimator is a subset of instrumental variable method estimators. In this method, in addition to solving the problem of correlation of the independent variable with disturbance components, the endogeneity of the variables and the heterogeneity of the variance of the model are also solved. It should be noted that this method is applicable when T is smaller than N (number of segments).

The results of this research show that the economic complexity index affects the development of renewable energy in developing and developed countries and also causes a decrease in the use of non-renewable energy and total energy consumption in developed countries and an increase in the use of non-renewable and total energy consumption in developing countries. It is currently being developed. In this research, the opening of trade has had a positive effect on the consumption of renewable energy in both groups of countries, and in developed countries, the opening of trade has reduced the consumption of non-renewable and total energy, and in developing countries, the opposite result has been obtained. In both groups of countries, energy consumption has a positive relationship with income level. Also, the results show that if economic growth is accompanied with higher technology, it can lead to a lower increase in total energy consumption in both groups of countries.

As mentioned in the introduction, economic complexity represents a complex and knowledge-based production structure of a given country that takes a long time to mature. When economic complexity increases, the use of non-renewable energy and environmental degradation increases first in a given country. However, with the increase of environmental preferences in a society, the economic actors change their energy by using non-renewable energy habits. This is completely consistent with the results of the estimation models as explained above. Based on the obtained results, it can be said that economic complexity is a policy factor for the overall transformation of renewable energy and demand for greener energy. The study recommends that complexity and structural change policies should be implemented for cleaner and greener growth and overall promotion of greener energy in developing and developed countries. Due to the movement of developing countries towards the development of technology, the need for energy will increase in the coming years. Hence, there is a need for policymakers to plan to meet energy needs. Considering the existing limitations in the use of fossil energy, which leads to complications such as environmental pollution and resource depletion, necessary investments should be made for the development of clean and renewable energy. In order to reduce energy consumption, policies that increase energy efficiency or prevent any form of  waste should be formulated, especially in economic sectors. In this regard, Can and Guzgur recommend that the level of fossil energy consumption in each industry should be clearly estimated and based on that, governments should establish specific laws for each industry. Through developing policies related to trade facilitation, they should also reduce the cost of importing new technologies, or decrease the cost of discovering new technologies via financing research and development institutions. Governments should promote energy regulations to reduce fossil fuel dependence and energy intensity. Future studies could examine the impact of economic complexity on energy demand in terms of oil-importing versus oil-exporting economies. Examining the effects of economic complexity on different aspects of energy (e.g., electric and nuclear energy) can be an important research question for researchers working on energy strategy.

Today, benefits from energy sources, especially non-renewable sources, can have various effects on economic indicators, and for this reason, it has risks for the economy and society. One of these important economic indicators is income inequality, which over time leads to many problems for societies. In this research, the effect of dependence on non-renewable natural resources on the income inequality of developed countries has been investigated. This dependence has been re-examined by separating non-renewable resources into fossil and non-fossil resources. The data of the study was collected from 25 developed countries during the years 1990 to 2019, and after making sure that no false regressions occurred during the estimation, an econometric study was conducted between the variables. According to the short-term and long-term estimation results obtained from the consolidated group average approach, it was determined that although in the short-term dependence on natural resources has no effect on income distribution, in the long-term two variables dependence on total non-renewable natural resources and dependence on fossil non-renewable natural resources have a negative effect and Significant as well as the variable of dependence on non-renewable non-fossil natural resources had a negative and insignificant effect on inequality. It was also determined that the control variables used such as: education, globalization and institutional quality can reduce income inequality in developed countries.

Renewable energy sources including Energies of wind, solar, water, biomass, geothermal, marine and other non-fossil energy play a very important role in energy security, social and economic development, access to energy, ensuring energy supply in the long term, they reduce climate change and reduce environmental and health effects. Todays, due to the importance of using renewable energy instead of fossil energy, many countries are seeking to replace their energy sources by passing laws and regulations and adopting incentive and support policies.
In this paper, the researchers are using the library research method to study the comparative laws and regulations and examine the programs and policies encouraging the development of wind, solar, hydroelectricity and biomass energy in the European Union.
 China and the United States are as the main renewable electricity technologies common in each country. It deals with three countries and examines the legal requirements for the expansion and development of renewable energy in these countries.

Based on the theoretical literature, there are different and contradictory approaches about the effect of shadow economy on per capita income. So, according to the importance of this issue for proper policy-making, this study examines the effect of the shadow economy on per capita income in the period 2005 to 2017 using the PARDL method in two groups of developing and developed countries in the short and long term. According to the results in the short run, the shadow economy has a significant and negative impact on per capita income in both set of countries. In the long term, the effects of this variable on per capita income in developed countries is insignificant, but in the developing countries have been significant, and its effect is greater than short term. Thus, developed countries have the ability to control the negative effects of the shadow economy on per capita income in the long run, while for developing countries, the negative effects have increased in the long run.

Technological innovation is one of the key indicators for economic growth and productivity. Recent studies show that R&D investment causes technological change. However, this relationship is not always obvious and seems to vary according to the level of economic development. A large number of studies on developed countries confirm the positive relationship between research and development, innovation and productivity. However, in developing countries, this relationship is not always clear. In this regard, in order to allocate an important share of national income to research and development, developing economies need to achieve a high and sustainable economic growth rate or create an economic development policy based on new innovation. This paper investigates the threshold effect of medium-high technology exports on total factor productivity in 50 developing and developed countries over the period 2007-2020.

For analyzing data, panel smooth transition regression (PSTR) model is used, which was presented and expanded by Gonzalez et al. (2005) and Colletaz & Hurlin (2006) and is very suitable for heterogeneous panel data. Thus, Medium-High Technology Exports index is chosen as the transition variable. Following the study of Hammar and Bellarebi (2021), the general model shows the relationship between the logarithm of total factor productivity, the logarithm of advanced and medium exports (transition variable), the logarithm of trade openness, and the logarithm of research and development expenditures.

The results show a nonlinear relationship between the variables under study. Based on the necessary test results, considering only one transition function with a threshold value and two regimes is sufficient for nonlinear estimation of the model. Also, the logarithm of the value of the transition variable threshold is estimated about 3.0816 and the slope parameter is estimated about 6.4226. Research and development (R&D) expenditures and trade have negative significant effects on total factor productivity in the first regime on total factor productivity that this effect by crossing the threshold (Medium-High Technology Exports) effect for the variable of R&D expenditures becomes positive and insignificant. This result is consistent with the study of Sepherdoost and Afshari (2016). In addition, the results show that the influence of trade on total factor productivity is negative and significant, but its influence is lower than before, in the second regime. This result is consistent with the study of Lotfalipour et al. (2015)

Considering the role of high and medium technology exports in the relationship between research and development expenditures and total factor productivity, it can be said that developing countries in the initial stages of growth can increase their productivity by increasing the export of high technology industries, to a level of specific development, despite the very high importance of research and development in the development of high-tech industries. Only a very small part of the country's resources is spent on research and development, and the weakness of the workforce has reduced the utilization of this small amount of domestic research and development investment. So, the low contribution of research and development expenses indicates that companies do not have much desire for innovative efforts and the creation of new technology transfer capacity as a stimulus for the quantitative and qualitative growth of industrial products. This action has caused them to not provide new products and services and reduce their competitiveness in domestic and foreign markets.The most important policy recommendation is that the governments of developing countries should develop high and medium technology exports witch through their positive effects such as productivity growth, reduction of production costs, improvement of financial development and growth of innovation and technology, it is possible to achieve favorable economic growth and to improve the productivity of all factors. Also, the development of exports with advanced and medium technology and knowledge-based production will initially attract educated and specialized unemployed people, and with the improvement of management practices, the productivity of production factors and the level of technology will increase and lead to product innovation. Therefore, considering the importance of exporting with advanced and medium technology and knowledge-based production, it is suggested that the universities move towards the third generation university, in which case the chain of knowledge to technology will be completed in the university and the university will support the industries by developing the latest technologies. It is also suggested that in order to improve their competitiveness in the international arena and to advance their development goals, developing countries allocate a greater share of their income resources to research and development and create incentives for researchers in various economic sectors, especially in industries with technological capabilities, and move more towards the knowledge-based economy and the implementation of research policies based on innovation.

The purpose of this article is to investigate how education affects happiness in selected developing and developed countries in the period 2005-2016. For this purpose, using dynamic and static panel methods, the factors affecting happiness with emphasis on training indicators have been estimated. The estimation results in selected developing countries have shown that preschool enrollment rate and elementary enrollment rate have no significant effect on happiness, but secondary enrollment rate and university enrollment rate have a significant negative effect on happiness. The estimation results in selected developed countries have also shown that the preschool enrollment rate has a significant positive effect on happiness, which shows the attention of the preschool education system in these countries to improve the level of happiness, but the primary enrollment rate, secondary enrollment and university enrollment rates did not have a significant effect on happiness. Therefore, in general, it can be concluded that the higher the level of education of individuals has caused the lower the happiness of individuals or at least did not have a significant effect on happiness. One of the reasons for this is that with the increase of education, a person's expected happiness becomes more gap with his realized happiness, because the promotion of education increases the level of expectations, and as a result, because the realized happiness does not increase in proportion to the expected happiness, improving the level of education will further reduce happiness. This finding could be another indication of the existence of the Easterlin paradox.

Appropriate distribution of income and reduction of inequality are one of the government’s goals. Different policies and tools are used to achieve this and the minimum wage is one of them. In this study, the effects of minimum wages on income distribution, due to the most similarities in development and per capita income were studied in 7 selected developing countries including (Pakistan, Armenia, Iran, Belarus, Chile, Egypt, Georgia) and 7 selected developed/development countries including (USA, France, Japan, Sweden, Netherlands, Belgium, and Canada) with generalized minimum squares from the years 2000 to 2020. The results show that, in developing and developed countries, an increase in the minimum wage, improves income distribution and the effects of this policy in developed countries are much greater than in developing countries. Therefore, developing and developed countries should increase the minimum wage in proportion to the rate of inflation to progress and improve income distribution.Appropriate distribution of income and reduction of inequality are one of the government’s goals. Different policies and tools are used to achieve this and the minimum wage is one of them. In this study, the effects of minimum wages on income distribution, due to the most similarities in development and per capita income were studied in 7 selected developing countries including (Pakistan, Armenia, Iran, Belarus, Chile, Egypt, Georgia) and 7 selected developed/development countries including (USA, France, Japan, Sweden, Netherlands, Belgium, and Canada) with generalized minimum squares from the years 2000 to 2020. The results show that, in developing and developed countries, an increase in the minimum wage, improves income distribution and the effects of this policy in developed countries are much greater than in developing countries. Therefore, developing and developed countries should increase the minimum wage in proportion to the rate of inflation to progress and improve income distribution.

The overall purpose of this study is to examine the privatization experiences of developing and developed countries in agricultural research and modeling in the Iranian agricultural sector. In the first stage, the influential factors in privatization were identified using the cross-linked research method. For this purpose, 42 selected papers in internationally accredited journals in the period 2000-2018 were selected with a thematic focus on privatization and agricultural research. In five separate stages, the objectives, samples, research method, findings and results were selected. The results of this phase resulted in the separation of five key factors in privatization. The factors were 1) Causes of privatization tendency: to increase efficiency, improve government finances, expand capital markets, reduce costs, create employment, and reduce administrative bureaucracy 2) Privatization Barriers: Component Political and legal uncertainties, strong stakeholder opposition, government financial weakness, high unemployment, increased competition in world markets, inflation control, and reduced government tenure. 3) Privatization Disadvantages: Component the reluctance to provide services in disadvantaged areas, ignoring environmental issues, reducing government control over the type and quality of service provision, and the existence of insecure employment contracts 4) Solutions Privatization: Including equity, direct selling of assets, contracting, and restructuring of the consumer market. 5) Consequences of privatization: Increasing efficiency, improving government finances, reducing costs, creating employment and reducing bureaucracy. In the second phase of the research, using the qualitative research method by grounded theory, the five main factors identified were coded in three stages and the proposed model of agricultural privatization in Iran was put together to bring together the contexts, causes, solutions and consequences.

Globalization is an undeniable phenomenon that affects all variables and indicators of countries not only economically but also politically and socially. Countries that cannot accept this phenomenon will be deprived of their blessings. The insurance industry is one of the most important outlines of the financial development triangle that is affected by the phenomenon of globalization. Over the past 30 years, globalization in business markets has developed so much that its role in the financial markets cannot be denied. The time and place barriers that insurers and reinsurers defined for themselves no longer make sense. Facilitating the process of globalization in the insurance industry allows international insurance companies to have an active presence in the markets of developed countries, especially developing countries, which warms the competition between domestic and international insurers. The phenomenon of globalization in developing countries can have different effects on the insurance industry, which can lead to the development of the insurance industry in the face of international competition or weaken the insurance industry in developing countries. Considering the importance of the subject in the present study, the effect of globalization on the insurance industry in the "developing countries of the Iran Vision Region" and "developed countries" is comparatively investigated.

Theoretical framework:

Many studies have been conducted to investigate the impact of globalization indicators on economic, social, political, etc. variables, which often point to the importance of this phenomenon. Some studies have also cited this phenomenon as a threat to some developing societies. There have been few studies on the impact of globalization on the insurance industry that has been mentioned in the literature of the present study. . The results of this research also point to the positive and significant effects of this phenomenon on the insurance industry. Successful examples of this phenomenon in the insurance industry include the performance of large international insurance companies such as AXA and Allianz in Mena countries, which have a large share of the market in these countries. They have also led to the growth of domestic insurance companies.The contradictory results of earlier studies on the impact of globalization on the insurance industry in developed countries and emerging markets show the need for the present study to see whether emerging countries stand up to this phenomenon to support the national insurance industry or, like developed countries. Pave the way for globalization. The contradictory results of earlier studies on the impact of globalization on the insurance industry in developed countries and emerging markets show the need for the present study. Should emerging countries stand up to globalization in order to support the national insurance industry? Or support globalization like developed countries. In the present study, using the mathematical model, the effect of globalization not only economically but also politically, socially, and in general on the penetration of insurance by life, non-life, and general insurance in the two groups of selected developed countries and groups of countries. Iran's perspective is examined.

In the present study, based on standard econometric methods such as panel data  and by using Eveiws and STATA software, we estimate the model and based on the results, we propose policies to develop the insurance industry. The following mathematical models are derived from the combined economic models of studies (Chiang & Yi-Bin, 2016), (AsadiGharagoz, et al., 2017) and (Williams & Balcilar, 2020). The mathematical and conceptual model of the research is described in 

In developed countries, social globalization, general globalization, political globalization, and economic globalization have had the greatest impact on insurance penetration in general, respectively. The degree of significance of all variables of globalization in explaining the changes in the penetration rate of general insurance has been at the level of 99%. But in "Iran Vision Countries", globalization, political globalization, and economic globalization, respectively, have had the greatest impact on insurance penetration in general. Among these, economic globalization and general globalization, respectively, had the highest significance at the level of 0.95% in explaining changes in insurance penetration. Examination of the both intensity and degree of significance, we come to the conclusion that the intensity of the impact of globalization on insurance penetration in developed countries is higher than in Iran. In developed countries, the social dimension of globalization and in the perspective countries of Iran, the economic dimension of globalization has had the greatest and most significant effect on insurance penetration. By carefully examining the effect of the dimensions of globalization on the penetration rate of life and non-life insurance, we will reach more accurate results from this study.In developed countries, respectively, economic globalization, social globalization, and globalization have the greatest impact on reducing the penetration rate of non-life insurance. But in the "Iran Vision" countries, political, general and economic globalization, respectively, have had the greatest impact on increasing the penetration rate of non-life insurance.Comparatively reviewing the results, we conclude that in developed countries, economic globalization has the greatest impact on reduction and in the countries of "Iran Vision" and Iran, political globalization has the greatest impact on the penetration rate of non-life insurance.

Conclusions & Suggestions:

1- Determinates of the least portfolio for life insurance premiums by the Central Insurance for insurance companies: Due to the restrictions announced by Central Insurance, insurance companies make their advertising, educational and cultural efforts to increase the penetration rate of insurance they live.2- By developing international relations, the government can pavé the way for international insurance companies to enter the country: This policy of expansion causes the insurance industry to develop in two dimensions: "FPI" and transfer of technical knowledge.3- Developing the supply of insurance services in deprived areas4- Inflation control and population control policies by the government in conditions of stagflation

In recent years, some research has focused on the importance of the origin of an oil shock for macroeconomic dynamics in both oil-exporting and importing countries. The existing literature lacks a proper open Stochastic Dynamic General Equilibrium (DSGE) framework to investigate the effect of the origins of oil shocks on macro variables in a two-country model consisting of an oil-exporting county and an oil-importing country. To this end, we develop and solve a new Keynesian DSGE model to show how the different oil shocks originating from oil supply or oil demand, might have diverse impacts on key macroeconomic variables in oil-exporting and importing counties. For the case study, we use data from Iran as an example of an oil-exporting country that trades with the rest of the world. Our DSGE model is estimated by using the Bayesian method for the period 1986:1-2017:4. The result shows that an oil shock originated from the shortage of oil supply (an exogenous decrease in Iran's oil production) decreases total production, non-oil trade, employment, inflation and consumption in this oil-exporting country. While a negative oil supply shock increases production costs and reduces production and consumption in Iran. However, an oil shock originated from an increase in the demand for oil raises output, non-oil trade, employment, consumption, and inflation in Iran as an oil-exporting country while a demand-side oil shock boosts production and increases inflation in this country.

This study examines the relationship between per capita income and per capita dioxide emissions in the form of a new definition of the Environmental Kuznets Curve, to investigate how corruption influences the income level at the turning point of the relationship between per capita dioxide emissions and income, in developed and developing countries the period 1994-2013 through the use of a panel data model. Our results support the Environmental Kuznets Curve hypothesis for developed countries and existence of an U-shaped relation for developing countries. We find evidence that the higher the country's degree of corruption, the higher the per capita income at the turning point for developed countries and the lower the per capita income at the turning point for developing countries than when corruption is not accounted for. Also, the share of renewable energy in both groups of countries has a negative and significant effect on per capita dioxide emissions, but the positive effect of urbanization rate in developed countries is significant and in developing countries is not.

This paper uses dynamic panel data and generalized method of moments to investigate the direct and indirect effects of corruption on carbon dioxide emissions for the period 2003 to 2012 in developed and developing countries. The results of the estimation indicate that corruption has a negative direct effect on CO2 emission through undermining enforcement of environmental regulations and a positive indirect effect through its negative impact on per capita GDP in developed and developing countries.The total effect, depends on the income level of the countries. Our study confirms the existence of an inverted U-shaped Environmental Kuznets Curve between CO2 emissions and GDP for developed countries and a U-shaped relation for developing countries. In the case of other variables, the lag of the dependent variable, the degree of openness of the economy and the energy consumption in both groups have a positive effect on the relationship between CO2 emissions and GDP, while the share of renewable energy has a negative effect.
JEL Classification: D73، Q53، C33

The main challenge of developing countries is to achieve growth and development. The extant economic growth literature illustrates that the quality of institutions and social infrastructure are important factors that influence the economic growth and development. Accordingly, many analysts believe that regarding such institutional factors, the rule of law is one of the most prominent aspects necessary for a system to achieve investment and economic growth. This study aims to investigate the impact of institutional variables on economic growth in developed and developing countries for the period 1995-2015. To this end, Panel Smooth Transition Regression (PSTR) model has been used. The estimation results of model reject the linearity hypothesis, and estimate a model with two regimes that proposes a threshold at institutional quality indicators of 0.1627 and 0.625 for the countries under study. It is demonstrated that the factor of rule of law has a positive impact on economic growth; however, this impact is higher in the second regime. The results also show that in both regimes, the variables of institutional quality indices, economic freedom, human capital and other control variables have a positive effect on economic growth. Moreover, the intensity of the variables influencing the changes in both groups intensifies when institutional quality improves.

In economic literature and especially in international economy literature, Feldstein and Hori Oka puzzle (briefly: F-H puzzle) has special consideration. According to F-H puzzle, in countries which have high international capital mobility, there is a positive but weak meaningful statically correlation between investment rate and domestic saving rate. We investigate threshold impact of saving rate on investment rate in selected developed and developing countries during 1995-2012 due to experiment F-H puzzle. We used Panel Smooth Transition Regression (PSTR) Model in order to study F-H puzzle in these countries. The results of linear relationship test strongly confirm nonlinear relationship between variables of the paper. According to the estimate results, threshold limit of saving calculated (for developed countries: 17.8 and for developing countries: 32) and slope parameter (Transfer Rate) also accounted (for developed countries: 0.1 and for developing countries: 10.3). In developed and developing countries saving rate has positive and meaningful statically effect on investment growth in both regimes. However in developing countries saving rate has less [positive and meaningful statically] effect on investment growth than developed countries. Paper results reject F-H puzzle in both developed and developing countries.