Convergence Hypothesis Research Articles

Parallel host shifts in a bacterial plant pathogen suggest independent genetic solutions.

While there are documented host shifts in many bacterial plant pathogens, the genetic foundation of host shifts is largely unknown. Xylella fastidiosa is a bacterial pathogen found in over 600 host plant species. Two parallel host shifts occurred-in Brazil and Italy-in which X.fastidiosa adapted to infect olive trees, whereas related strains infected coffee. Using 10 novel whole-genome sequences from an olive-infecting population in Brazil, we investigated whether these olive-infecting strains diverged from closely related coffee-infecting strains. Several single-nucleotide polymorphisms, many derived from recombination events, and gene gain and loss events separated olive-infecting strains from coffee-infecting strains in this clade. The olive-specific variation suggests that this event was a host jump with genetic isolation between coffee- and olive-infecting X.fastidiosa populations. Next, we investigated the hypothesis of genetic convergence in the host shift from coffee to olive in both populations (Brazil and Italy). Each clade had multiple mutations and gene gain and loss events unique to olive, yet no overlap between clades. Using a genome-wide association study technique, we did not find any plausible candidates for convergence. Overall, this work suggests that the two populations adapted to infect olive trees through independent genetic solutions.

A club convergence analysis of financial integration: cross-country evidence

PurposeThe purpose of this study is to examine the club convergence of Financial integration (FI) in the case of 60 countries from 1970 to 2015. FI plays a vital role in economic growth through sharing the risk between countries, cross-border capital association, investment and financial information. It also leads to the efficient allocation of capital and capital accumulation, thereby improving the systematic growth and productivity of the economy. Literature on examining the convergence hypothesis of FI is scarce.Design/methodology/approachThis study applies the clustering algorithm to identify club convergence, advanced by the Phillips and Sul test, which enables the identification of multiple steady states or club convergence, unlike beta and sigma convergences.FindingsThe findings indicate the non-convergence when all 60 countries were taken together. This highlights that the selected countries' have unique transition paths in terms of FI. Hence, the authors implement the clustering algorithm, and the estimation shows that 56 countries are categorised into three different clubs. However, for the rest of four countries, the results are sort of ambiguous, favouring neither convergence nor divergence.Practical implicationsOn the basis of three country clubs, Club 1 presents the model countries such as the Netherlands, Singapore and Switzerland. The Club 2 and Club 3 countries can start making moves towards the model countries by making policy adaptations for trade, finance and business facilitation.Originality/valueThe existing literature provides a plethora of studies investigating the convergence of stock markets, exchange rates and equity markets, but studies on the convergence of FI, particularly across the countries, are scarce. This study contributes by bridging this gap. The study is unique in its type as it takes into account the multiple steady states or club convergence. This study also contributes in policymaking by suggesting Club 1 countries (the Netherlands, Singapore and Switzerland) as the model ones for the FI.

Convergence of economic growth and health expenditures in OECD countries: Evidence from non-linear unit root tests.

The relationship between human capital, health spending, and economic growth is frequently neglected in the literature. However, one of the main determinants of human capital is health expenditures, where human capital is one of the driving forces of growth. Consequently, health expenditures affect growth through this link. In the study, these findings have been attempted to be empirically tested. Along this axis, health expenditure per qualified worker was chosen as an indicator of health expenditure, and output per qualified worker was chosen as an indicator of economic growth. The variables were treated with the convergence hypothesis. Due to the non-linear nature of the variables, the convergence hypothesis was carried out with non-linear unit root tests. The analysis of 22 OECD countries from 1976 to 2020 showed that health expenditure converged for all countries, and there was a significant degree of growth convergence (except for two countries). These findings show that health expenditure convergence has significantly contributed to growth convergence. Policymakers should consider the inclusiveness and effectiveness of health policies while making their economic policies, as health expenditure convergence can significantly impact growth convergence. Further research is needed to understand the mechanisms behind this relationship and identify specific health policies most effective in promoting economic growth.

IS TOURISM CONVERGENCE VALID IN TURKEY? EVIDENCE FROM FURUOKA UNIT ROOT TEST

The positive effects of tourism on the economy are gradually increasing. These positive effects force countries to seek new policies to develop the tourism sector further. Turkey has a critical position in the tourism sector, and its main policy in this area is to increase its income. This study purpose of testing the validity of the convergence hypothesis for the countries located in different continents of the world in Turkey's international tourism market. The study covering the years 2000-2020 analyzed eight groups (Africa, America, Asia, Europe, Independent States, OECD, Oceania and non-national) with the data created by the Turkish Statistical Institute (TUIK). The unit root test developed by Furuoka (2017) is used to test the validity of the convergence hypothesis. As a result of this study found model D to be the most appropriate method among the four proposed alternatives. Accordingly, it is seen that the convergence is not valid for Asia, Europe and Oceania. It is also concluded that convergence is valid for America, OECD, Non-National, Independent States and Africa.

Regional convergence and catching up process in Africa: A tale of three clubs

AbstractThe aims of this article were twofold. First, to tackle the issue of convergence from an analytical point of view by presenting the mathematical developments of the main economic growth models, which emphasized that the convergence of African economies is conditional to the investment level in the early stages of physical capital accumulation. As the latter increases, the convergence of African economies is determined by other factors (investment in research and development (R&D) and human capital, etc.). Second, to verify the empirical validity of these models by confronting them with data from 33 African economies stratified by development level over the period 2004–2019. Empirical results using both spatial and nonspatial panel estimation methodology and the ‘beta‐convergence’ approach pointed to three ‘convergence clubs,’ as well as a conditional convergence for all these clubs. However, the determinants of convergence among African economies differ by development level. In low‐income economies, convergence is conditional to financial development and inflation level. For lower‐middle‐income economies, institutional quality and inflation level contribute to the convergence of this club. The convergence of upper‐middle‐income economies is conditioned by public spending and human capital. In terms of policy implications, countries should develop measures that strengthen institutional reforms to improve the functioning of financial systems, democratic accountability, control of corruption, business climate, economic growth, strengthening the legal environment, and improving competition by reducing public expenditures. This paper is original insofar as it advances the field from the current state of knowledge in several ways. First, to stand out from the existing literature, we conducted a comparative analysis of the institutional quality levels across 33 African countries by developing an institutional quality index through the use of a principal component analysis (PCA) method. Second, we tested the empirical validity of the convergence hypothesis beneath economic growth theories and in the African context; moreover, it has verified the possible existence of ‘convergence clubs,’ then, it brought to light the main determinants of the convergence of these clubs.

Testing convergence hypothesis for EU countries: a heterogenous panel data approach

PurposeThis 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/approachThe study uses nonstationary heterogeneous panel-data methodology.FindingsThe 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/valueThe 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.

Revisiting the environmental Kuznets curve hypothesis with globalization for OECD countries: the role of convergence clubs.

This paper aims to investigate the role of globalization in ecological footprint for Organization for Economic Cooperation and Development (OECD) countries during the 1981-2015 period with the environmental Kuznets curve (EKC) framework. To do so, unlike the existing literature, we follow a different path. Firstly, we test the environmental convergence (EC) hypothesis using the Phillips and Sul, Econometrica 75(6): 1771-1855, (2007) methodology. Then, we examine the impact of globalization and energy consumption on the ecological footprint (EF), and test the existence of the EKC hypothesis using the dynamic ordinary least squares mean group (DOLSMG) estimator. The convergence test results indicate that OECD countries do not converge to the same steady-state levels with regard to EF levels. However, we identify two convergence clubs that converging to a different steady-state equilibrium. The results of DOLSMG reveal that the EKC hypothesis is valid for both convergence groups. Furthermore, the impact of energy consumption and globalization on EF is higher for club 2, which includes developing countries.

Is there convergence in renewable energy deployment? Evidence from a new panel unit root test with smooth and sharp structural breaks

This study examines whether the contribution of renewable energy to the total primary energy supply converges in a panel of 24 OECD countries over the period 1960–2020. To this end, a new panel unit root test that allows for both sharp and smooth breaks is proposed to test for the stochastic convergence hypothesis. Although renewable energy convergence is not rejected when the newly proposed test is applied to the full panel of OECD countries, it found only moderate support within the members of the panel using a sequential panel selection methodology. In fact, in two high-income OECD countries, the contribution of renewable energy to the primary energy supply shows no sign of convergence: Poland and Iceland. Therefore, the renewable energy shares seem to be converging to a common steady state in only a group of OECD countries over the long run. This uneven pattern of convergence, in turn, suggests that the OECD countries are still far away from developing a common sustainable renewable energy target, calling for urgent international policy cooperation to encourage the divergent economies to seek out the menu of policies that ensure the worldwide success of renewable energy transformation.

The Convergence in Greenhouse Gas Emissions Across G-7 Countries

Environmental degradation, such as climate crisis, global warming, etc., is one of the crucial issues for countries. Studies in the literature analyze the convergence in environmental degradation regarding the environmental convergence hypothesis using different indicators such as carbon dioxide emissions, ecological footprint, etc. to identify the differences in environmental quality across countries. This study tests the environmental convergence hypothesis for G-7 countries over the period 1997-2018. To do so, we use greenhouse gas emissions per capita as an indicator of environmental degradation and apply non-linear dynamic factor model developed by Phillips and Sul (2007). According to the results, countries do not converge to a single equilibrium point. However, Phillips and Sul (2007) convergence methodology allows us to identify possible convergence clubs. The club clustering algorithm identifies three convergence clubs, each converging to a different steady-state. Club 1, which converges to higher greenhouse gas emissions per capita level, includes Canada and United States, whereas Club 2 includes Germany and Japan, and Club 3 includes France, Italy, and the United Kingdom. The results confirm that the that the environmental convergence hypothesis does not hold for G-7 countries.

Inter-state disparities in government health expenditure in India: a study of national rural health mission

PurposeThe study aims to compare India's public health expenditure at the international and state levels. The paper also empirically examines the regional disparities in NRHM spending across the 21 selected states of India.Design/methodology/approachThe tools of absolute β-and σ-convergence are used in the analysis to test the regional convergence. The average annual growth rate across the states is the dependent variable for β-convergence, and time is the second dependent variable but is used for s-convergence. In contrast, the initial value of NRHM expenditure and the coefficient of variation of NRHM expenditure are used as independent variables, respectively. Descriptive statistics are also used for the study. The data are annual and cover the panel from 2007 to 2020.FindingsThe study attests to the hypothesis of β-and σ-convergence for the selected states in the period mentioned. The observed convergence in NRHM expenditure is due to the shift in the government's attention from the non-high focus high focus states to high states through the national rural health mission policy. The coefficient of variation across the states also shows a declining trend and provides the robustness of the σ-convergence.Originality/valueAs far as the literature is concerned, none of the existing studies examines the convergence of a public health expenditure scheme like the National Rural Health Mission across the Indian states by applying the techniques of β-and σ-convergence. The novelty of the study is using the newly updated dataset and validating the convergence hypotheses in the National Rural Health Mission expenditure case.

Does club convergence matter? Empirical evidence on inequality in the human development index among Indian states

The Human Development Index (HDI) is recognised as the most commonly used composite index to assess the socio-economic progress of a country. To preserve its pioneering role in development, there has to be a reduction in inequalities and cross-state convergence by adding a sustainable dimension. This paper investigates the convergence hypothesis for the HDI in 36 Indian states and union territories (UTs) from 1990 to 2019. For that purpose, the study used the club convergence technique of Phillips and Sul (2007) and Kernel Density estimates to assess whether states converge towards a single steady-state equilibrium or multiple groups. The paper also considers the relative performance of Indian states and UTs and the comprehension of inter-regional inequality in the HDI by employing the Gini and Theil indices. Using the Phillips and Sul technique, the results reveal that all the states converged into two final clubs (i.e., Club 1 and Club 2). The rate of convergence of HDI is approximately 0.112% for club 1 and 1.135% for club 2. The findings indicate that states with the lowest HDI converge faster than those with higher HDI. The kernel density estimates demonstrate that HDI stratifies, polarises, and becomes unimodal over time, albeit with a common steady state. Further, the Gini and Theil indices suggest a significant decline trend in HDI inequality across the Indian states and UTs from 1990 to 2019. From a policy perspective, the study recommends promoting regional development and reducing inequality, considering the unique convergence paths of the clustering states. The study’s findings could provide the government with a new perspective on attaining “horizontal equity” in HDI across Indian states and UTs.

Convergence Hypothesis: A Systematic literature Review with Bibliometric Analysis

Convergence Hypothesis: A Systematic literature Review with Bibliometric Analysis

Convergence hypothesis: a systematic literature review with bibliometric analysis

Convergence hypothesis: a systematic literature review with bibliometric analysis

A phenotype-structured model for the tumour-immune response

This paper presents a mathematical model for tumour-immune response interactions in the perspective of immunotherapy by immune checkpoint inhibitors (ICIs). The model is of the nonlocal integro-differential Lotka-Volterra type, in which heterogeneity of the cell populations is taken into account by structuring variables that are continuous internal traits (aka phenotypes) present in each individual cell. These represent a lumped “aggressiveness”, i.e., for tumour cells, malignancy understood as the ability to thrive in a viable state under attack by immune cells or drugs – which we propose to identify as a potential of de-differentiation–, and for immune cells, ability to kill tumour cells, in other words anti-tumour efficacy. We analyse the asymptotic behaviour of the model in the absence of treatment. By means of two theorems, we characterise the limits of the integro-differential system under an a priori convergence hypothesis. We illustrate our results with a few numerical simulations, which show that our model reproduces the three Es of immunoediting: elimination, equilibrium, and escape. Finally, we exemplify the possible impact of ICIs on these three Es.

Corrupt Clubs and the Convergence Hypothesis

Convergence is defined as the decreasing gap of GDP growth rates between leading and lagging countries. This thesis is based on the Veblen’s idea of “Advantages of Backwardness”. It states that a less developed country tends to grow, at a rate which is inversely proportional to its initial GDP per capita; that is, faster than more advanced countries. There are several reasons for this convergence across different countries. First, there is a scope for poor nations to absorb existing technology and to catch up advanced countries if the gap between country’s technologies is larger. Second, the development process is often characterised by a shift of resources from low productivity agriculture sector to high productivity industrial sector. The process certainly benefits more the poor nations because the capacity for such shift is more in poor countries than in rich countries.1

Convergence Clubs in the Brazilian Beef Market

The share of livestock in the Gross Domestic Product (GDP) of Brazilian agribusiness has considerable relevance in the country's economy. Specifically, the work tests the hypothesis of convergence and/or formation of price convergence clubs in each state, taking into account the possible technological differences existing among Brazil’s different regions. Data from 12 Brazilian states, from 2004 to 2021, is used. The methodology is the time series analysis, as featured in Phillips & Sul (2007). In club convergence, it is observed that in economies with similar initial conditions and identical structural characteristics, prices converge to the same long-term level. And, in this specific case, it was possible to identify only one convergence club, where all states follow the same pattern.

Is There a Grand Convergence in Child Undernutrition Reduction? Evidence from 183 Countries

ABSTRACT This study aimed to assess the progress of underweight, stunted, or wasted children across 183 countries from 1990 to 2015 using convergence models. Data for this study has been obtained from the World Bank Database and UNICEF (2020), which provides figures on underweight, stunting, and wasting prevalence for most countries. Data from national-level surveys were compiled for countries where the information was unavailable from the World Bank Database. For our empirical analysis, we have employed parametric convergence metrics like the absolute β-convergence model. In contrast, nonparametric convergence models such as Kernel density plots, were used as robustness checks for our primary analyses. The absolute-convergence model suggests a convergence in the progress of underweight and wasted children between 1990 and 2015, whereas we find a divergence in progress towards the decline in stunted children between 1990–95 to 2010–15. However, the nonparametric convergence test suggests that except for wasting, the other two indicators of child nutrition show an emergence of multiple convergence clubs instead of a grand global convergence. At the same time, the regional heterogeneity test for the absolute convergence model suggests that our main findings still hold except for stunting in upper-middle-income countries, which supports the convergence hypothesis.

Long‐term regional convergence in Mexico: A new look

AbstractThis paper explores the convergence hypothesis of Mexican states with the national level and with one another from 1940 to 2015. Interpreting convergence as catching‐up, we also capture other types of regular evolution, namely, invariance of the income gap over time, permanent absence of the gap, and steadily increasing gap (deterministic divergence). As a tool of econometric analysis, we use a novel model that describes convergence by asymptotically decaying trends and covers other types of evolution as particular cases. The results obtained suggest one or other type of regularity to be peculiar to roughly ca. 40% of income gaps both with the national level and between states. However, convergence is observed only in 6% to 15% of cases. Regarding convergence at the national level, an additional analysis by three 50‐year subperiod shows that in many cases the type of evolution changes for the same state from one subperiod to another. Analyzing convergence between states, we find that convergence between neighboring states is more frequent than between other states; however, the effect of the neighborhood is not too strong.

Reducing rural income inequality and its spatial convergence in China during the past two decades

Rural poverty and inequality are still big challenges for the world sustainable development. China has eliminated absolute poverty and reduced regional rural income inequality over the past two decades. To explain the spatial convergence of China’ rural income inequality, a comprehensive framework was proposed based on the convergence hypothesis. We examined the spatial convergence and influencing factors of rural income inequality using province-level panel data from 2001 to 2020. The findings showed that China's rural income inequality generally decreased from 2001 to 2010, the contribution rate of inter-regional rural income inequalities is he highest. There was a significant spatial β convergence of rural income change, indicating that rural income inequality in China has been effectively reduced and a catch-up effect has been created in low-income rural areas with a higher income growth rate. Social security and human capital factors play key roles in reducing regional rural inequality, especially in poor western regions. Meanwhile, China's targeted poverty alleviation policy amplified the positive impact on rural income convergence, and low-income regions benefited more from the policy. Then several suggestions were proposed for developing countries to reduce rural inequality and poverty.

Convergence analysis of science, technology, and environment expenditure: evidence from Indian states

PurposeThere is vast disparity in public expenditure on science, technology and environment (STE) across various Indian states. Public expenditure on STE is crucial in maintaining symmetric growth, social cohesion and sustainable development. Literature on this topic is scarce, which prompted the investigation of club convergence of STE public expenditure. In particular, the purpose of this paper to study the club convergence of STE public expenditure in the case of 20 Indian states during the period from 1987–1988 to 2019–2020.Design/methodology/approachThis study applies the clustering algorithm to identify club convergence, advanced by the Phillips and Sul test, which enables identification of multiple steady states or club convergence, unlike beta and sigma convergences.FindingsThe findings of this paper show that all Indian states do not converge towards single steady states. This suggests a disparity in STE public expenditure across Indian states. Moreover, the findings favour three clubs that have their own unique transition paths. The results of this study are supported by the robustness check.Practical implicationsThe findings suggest that the allocation of public expenditure on STE can be made based on club convergence to achieve social cohesion, sustainable development and millennium development goals across states.Originality/valueAlthough several previous studies have investigated the convergence of public expenditure by considering either aggregate public expenditure or health/education expenditure, literature on the convergence hypothesis of STE public expenditure, particularly across Indian states, is scarce. Moreover, this paper is unique, as it examines multiple steady states or club convergence. Finally, this paper contributes to policymaking by suggesting which states should be given a push to achieve social cohesion and sustainable development.