PUBLICATIONS
The AGDI has published substantially in fulfillment of its mission statement of contributing to knowledge towards African development:
IDEAS
http://ideas.repec.org/d/agdiycm.html
ECONSTOR
https://www.econstor.eu/dspace/escollectionhome/10419/123513
Publication List
2017 |
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| 441. | A, Nwachukwu Asongu J C S 2017. Links | BibTeX | Tags: Information sharing; Banking development; Africa @article{Asongu_438, author = {Nwachukwu J C Asongu S. A}, url = {http://www.afridev.org/RePEc/agd/agd-wpaper/Information-Asymmetry-and-Conditional-Financial-Sector-Development.pdf}, year = {2017}, date = {2017-07-11}, keywords = {Information sharing; Banking development; Africa}, pubstate = {published}, tppubtype = {article} } |
| 442. | Asongu, Jacinta Nwachukwu Simplice 2017. Abstract | Links | BibTeX | Tags: Economic growth, Financial Development, Financial instability and Africa @unpublished{Asongu_439, author = {Jacinta Nwachukwu Simplice Asongu}, url = {http://www.afridev.org/RePEc/agd/agd-wpaper/Linkages-between-finance-instability-liberalisation-and-growth-in-Africa.pdf}, year = {2017}, date = {2017-07-11}, abstract = {In the aftermath of the 2008 global financial crisis, the implications of financial liberalisation for stability and economic growth has come under increased scrutiny. One strand of literature posits a positive relationship between financial liberalisation and economic growth and development. However, others emphasise the link between financial liberalisation is intrinsically associated with financial instability which may be harmful to economic growth and development. This study assesses linkages between financial instability, financial liberalisation, financial development and economic growth in 41 African countries for the period 1985-2010. The results suggest that financial development and financial liberalisation have positive effects on financial instability. The findings also reveal that economic growth reduces financial instability and the magnitude of reduction is higher in the pre-liberalisation period compared to post-liberalisation period.}, keywords = {Economic growth, Financial Development, Financial instability and Africa}, pubstate = {published}, tppubtype = {unpublished} } In the aftermath of the 2008 global financial crisis, the implications of financial liberalisation for stability and economic growth has come under increased scrutiny. One strand of literature posits a positive relationship between financial liberalisation and economic growth and development. However, others emphasise the link between financial liberalisation is intrinsically associated with financial instability which may be harmful to economic growth and development. This study assesses linkages between financial instability, financial liberalisation, financial development and economic growth in 41 African countries for the period 1985-2010. The results suggest that financial development and financial liberalisation have positive effects on financial instability. The findings also reveal that economic growth reduces financial instability and the magnitude of reduction is higher in the pre-liberalisation period compared to post-liberalisation period. |
| 443. | E., Mlambo & Asongu Batuo K S A Research in International Business and Finance, 2017. Abstract | Links | BibTeX | Tags: Economic Growth; Financial Development; Financial instability and Africa @article{Asongu_440, author = {Mlambo & Asongu K S A Batuo E.}, url = {http://www.sciencedirect.com/science/article/pii/S027553191730452X}, doi = {10.1016/j.ribaf.2017.07.148}, year = {2017}, date = {2017-07-10}, journal = {Research in International Business and Finance}, abstract = {In the aftermath of the 2008 global financial crisis, the implications of financial liberalisation for stability and economic growth has come under increased scrutiny. One strand of literature posits a positive relationship between financial liberalisation and economic growth and development. However, others emphasise the link between financial liberalisation is intrinsically associated with financial instability which may be harmful to economic growth and development. This study assesses linkages between financial instability, financial liberalisation, financial development and economic growth in 41 African countries for the period 1985-2010. The results suggest that financial development and financial liberalisation have positive effects on financial instability. The findings also reveal that economic growth reduces financial instability and the magnitude of reduction is higher in the pre-liberalisation period compared to post-liberalisation period.}, keywords = {Economic Growth; Financial Development; Financial instability and Africa}, pubstate = {published}, tppubtype = {article} } In the aftermath of the 2008 global financial crisis, the implications of financial liberalisation for stability and economic growth has come under increased scrutiny. One strand of literature posits a positive relationship between financial liberalisation and economic growth and development. However, others emphasise the link between financial liberalisation is intrinsically associated with financial instability which may be harmful to economic growth and development. This study assesses linkages between financial instability, financial liberalisation, financial development and economic growth in 41 African countries for the period 1985-2010. The results suggest that financial development and financial liberalisation have positive effects on financial instability. The findings also reveal that economic growth reduces financial instability and the magnitude of reduction is higher in the pre-liberalisation period compared to post-liberalisation period. |
| 444. | S., & Asongu Tchamyou S A V 2017. Abstract | Links | BibTeX | Tags: Mutual funds; Market timing; Thresholds; Quantile regression @unpublished{Asongu_441, author = {& Asongu S A Tchamyou V. S.}, url = {http://www.afridev.org/RePEc/agd/agd-wpaper/Conditional-Market-Timing-in-the-Mutual-Fund-Industry.pdf}, year = {2017}, date = {2017-07-10}, abstract = {This study complements the scarce literature on conditional market timing in the mutual fund industry by assessing determinants of market timing throughout the distribution of market exposure. It builds on the intuition that the degree of responsiveness by fund managers to investigated factors (aggregate liquidity, information asymmetry, volatility and market excess return) is contingent on their levels of market exposure. To this end, we use a panel of 1467 active open-end mutual funds for the period 2004-2013. Fund-specific time-dynamic beta is employed and we avail room for more policy implications by disaggregating the dataset into market fundamentals of: equity, fixed income, allocation and tax preferred. The empirical evidence is based on Quantile regressions. The following findings are established. First, there is consistent positive threshold evidence of volatility and market return in market timing, with the slim exception of allocation funds for which the pattern of volatility is either U- or S-shaped. Second, the effect of volatility and market return are consistently positive and negative respectively in the bottom and top quintiles of market exposure, but for allocation funds. Third, the effects of information asymmetry and aggregate liquidity are positive and negative, contingent on specifications, level of market exposure and market fundamentals. The findings broadly suggest that blanket responses of market exposures to investigated factors are unlikely to represent feasible strategies for fund managers unless they are contingent on initial levels of market exposure and tailored differently across ‘highly exposed’-fund managers and ‘lowly exposed’-fund managers. Implications for investors and fund managers are discussed.}, keywords = {Mutual funds; Market timing; Thresholds; Quantile regression}, pubstate = {published}, tppubtype = {unpublished} } This study complements the scarce literature on conditional market timing in the mutual fund industry by assessing determinants of market timing throughout the distribution of market exposure. It builds on the intuition that the degree of responsiveness by fund managers to investigated factors (aggregate liquidity, information asymmetry, volatility and market excess return) is contingent on their levels of market exposure. To this end, we use a panel of 1467 active open-end mutual funds for the period 2004-2013. Fund-specific time-dynamic beta is employed and we avail room for more policy implications by disaggregating the dataset into market fundamentals of: equity, fixed income, allocation and tax preferred. The empirical evidence is based on Quantile regressions. The following findings are established. First, there is consistent positive threshold evidence of volatility and market return in market timing, with the slim exception of allocation funds for which the pattern of volatility is either U- or S-shaped. Second, the effect of volatility and market return are consistently positive and negative respectively in the bottom and top quintiles of market exposure, but for allocation funds. Third, the effects of information asymmetry and aggregate liquidity are positive and negative, contingent on specifications, level of market exposure and market fundamentals. The findings broadly suggest that blanket responses of market exposures to investigated factors are unlikely to represent feasible strategies for fund managers unless they are contingent on initial levels of market exposure and tailored differently across ‘highly exposed’-fund managers and ‘lowly exposed’-fund managers. Implications for investors and fund managers are discussed. |
| 445. | Asongu, Joseph Amankwah-Amoah Simplice A 2017. Abstract | Links | BibTeX | Tags: Capital flight; military expenditure; terrorism; Africa @unpublished{Asongu_442, author = {Joseph Amankwah-Amoah Simplice A. Asongu}, url = {http://www.afridev.org/RePEc/agd/agd-wpaper/Mitigating-capital-flight-through-military-expenditure.pdf}, year = {2017}, date = {2017-07-10}, abstract = {The purpose of this study is to assess the thresholds at which military expenditure modulates the effect of terrorism on capital flight. We employed a panel data of 37 African countries from 1996-2010.The empirical evidence was based on: (i) baseline contemporary and non-contemporary OLS, (ii) contemporary and non-contemporary fixed effects regressions to account for the unobserved heterogeneity, (iii) the Generalised Method of Moments to account for the capital flight trap and (iv) Quantile Regressions (QR) to account for initial levels of capital flight. The study found that the thresholds are apparent exclusively in Quantile Regressions with military expenditure thresholds ranging from: 4.224 to 5.612 for domestic terrorism, 5.734 to 7.363 for unclear terrorism and 4.710 to 6.617 for total terrorism. No thresholds are apparent in transnational terrorism related regressions. Depending on the terrorist target, the findings broadly show that a critical mass of between 4.224 and 7.363 of military expenditure as a percentage of GDP is needed to reverse the negative effect of terrorism on capital flight. In spite of the growing consensus of the need to utilise military expenditure to help combat terrorism, our understanding of the threshold at which military expenditure completely dampens the negative effect of terrorism on capital flight remains largely underexplored. We capitalize on panel data of 37 African countries to address this lacuna in our understanding of this important issue.}, keywords = {Capital flight; military expenditure; terrorism; Africa}, pubstate = {published}, tppubtype = {unpublished} } The purpose of this study is to assess the thresholds at which military expenditure modulates the effect of terrorism on capital flight. We employed a panel data of 37 African countries from 1996-2010.The empirical evidence was based on: (i) baseline contemporary and non-contemporary OLS, (ii) contemporary and non-contemporary fixed effects regressions to account for the unobserved heterogeneity, (iii) the Generalised Method of Moments to account for the capital flight trap and (iv) Quantile Regressions (QR) to account for initial levels of capital flight. The study found that the thresholds are apparent exclusively in Quantile Regressions with military expenditure thresholds ranging from: 4.224 to 5.612 for domestic terrorism, 5.734 to 7.363 for unclear terrorism and 4.710 to 6.617 for total terrorism. No thresholds are apparent in transnational terrorism related regressions. Depending on the terrorist target, the findings broadly show that a critical mass of between 4.224 and 7.363 of military expenditure as a percentage of GDP is needed to reverse the negative effect of terrorism on capital flight. In spite of the growing consensus of the need to utilise military expenditure to help combat terrorism, our understanding of the threshold at which military expenditure completely dampens the negative effect of terrorism on capital flight remains largely underexplored. We capitalize on panel data of 37 African countries to address this lacuna in our understanding of this important issue. |
| 446. | S., Asongu Tchamyou S A V Research in International Business and Finance, 2017. Abstract | Links | BibTeX | Tags: Mutual funds; Market timing; Thresholds; Quantile regression @article{Asongu_443, author = {Asongu S A Tchamyou V. S.}, url = {http://www.sciencedirect.com/science/article/pii/S027553191630469X}, doi = {10.1016/j.ribaf.2017.07.072}, year = {2017}, date = {2017-07-09}, journal = {Research in International Business and Finance}, abstract = {This study complements the scarce literature on conditional market timing in the mutual fund industry by assessing determinants of market timing throughout the distribution of market exposure. It builds on the intuition that the degree of responsiveness by fund managers to investigated factors (aggregate liquidity, information asymmetry, volatility and market excess return) is contingent on their levels of market exposure. To this end, we use a panel of 1467 active open-end mutual funds for the period 2004-2013. Fund-specific time-dynamic beta is employed and we avail room for more policy implications by disaggregating the dataset into market fundamentals of: equity, fixed income, allocation and tax preferred. The empirical evidence is based on Quantile regressions. The following findings are established. First, there is consistent positive threshold evidence of volatility and market return in market timing, with the slim exception of allocation funds for which the pattern of volatility is either U- or S-shaped. Second, the effect of volatility and market return are consistently positive and negative respectively in the bottom and top quintiles of market exposure, but for allocation funds. Third, the effects of information asymmetry and aggregate liquidity are positive and negative, contingent on specifications, level of market exposure and market fundamentals. The findings broadly suggest that blanket responses of market exposures to investigated factors are unlikely to represent feasible strategies for fund managers unless they are contingent on initial levels of market exposure and tailored differently across ‘highly exposed’-fund managers and ‘lowly exposed’-fund managers. Implications for investors and fund managers are discussed.}, keywords = {Mutual funds; Market timing; Thresholds; Quantile regression}, pubstate = {published}, tppubtype = {article} } This study complements the scarce literature on conditional market timing in the mutual fund industry by assessing determinants of market timing throughout the distribution of market exposure. It builds on the intuition that the degree of responsiveness by fund managers to investigated factors (aggregate liquidity, information asymmetry, volatility and market excess return) is contingent on their levels of market exposure. To this end, we use a panel of 1467 active open-end mutual funds for the period 2004-2013. Fund-specific time-dynamic beta is employed and we avail room for more policy implications by disaggregating the dataset into market fundamentals of: equity, fixed income, allocation and tax preferred. The empirical evidence is based on Quantile regressions. The following findings are established. First, there is consistent positive threshold evidence of volatility and market return in market timing, with the slim exception of allocation funds for which the pattern of volatility is either U- or S-shaped. Second, the effect of volatility and market return are consistently positive and negative respectively in the bottom and top quintiles of market exposure, but for allocation funds. Third, the effects of information asymmetry and aggregate liquidity are positive and negative, contingent on specifications, level of market exposure and market fundamentals. The findings broadly suggest that blanket responses of market exposures to investigated factors are unlikely to represent feasible strategies for fund managers unless they are contingent on initial levels of market exposure and tailored differently across ‘highly exposed’-fund managers and ‘lowly exposed’-fund managers. Implications for investors and fund managers are discussed. |
| 447. | A., Kodila-Tedika Asongu O S South African Journal of Economics, 2017. Abstract | Links | BibTeX | Tags: Africa; Genetic diversity; Comparative economic development @article{Asongu_444, author = {Kodila-Tedika O Asongu S. A.}, url = {http://onlinelibrary.wiley.com/doi/10.1111/saje.12165/full}, doi = {10.1111/saje.12165/full}, year = {2017}, date = {2017-07-08}, journal = {South African Journal of Economics}, abstract = {A 2015 World Bank report on attainment of Millennium Development Goals concludes that the number of extremely poor has dropped substantially in all regions with the exception of Sub-Saharan Africa. We assess if poverty is in the African gene by revisiting the findings of Ashraf and Galor and reformulating the “Out of Africa Hypothesis” into a “Genetic Diversity Hypothesis” for a “Within Africa Analysis.” We motivate this reformulation with five shortcomings largely drawn from the 2015 findings of the African Gerome Variation Project, notably: limitations in the conception of space, an African dummy in genetic diversity, linearity in migratory patterns, migratory origins and underpinnings of genetic diversity in Africa. Ashraf and Galor have concluded that cross-country differences in development can be explained by genetic diversity in a Kuznets or inverted U-shaped pattern. Our results from an exclusive African perspective partially confirm the underlying hypothesis in a contemporary context, but not in the historical analysis. From a historical context, the nexus is U-shaped for migratory distance, mobility index and predicted diversity while for the contemporary analysis; it is hump shaped for ancestry-adjusted predicted diversity. Hence from a within-Africa comparative standpoint, poverty is not in the African gene.}, keywords = {Africa; Genetic diversity; Comparative economic development}, pubstate = {published}, tppubtype = {article} } A 2015 World Bank report on attainment of Millennium Development Goals concludes that the number of extremely poor has dropped substantially in all regions with the exception of Sub-Saharan Africa. We assess if poverty is in the African gene by revisiting the findings of Ashraf and Galor and reformulating the “Out of Africa Hypothesis” into a “Genetic Diversity Hypothesis” for a “Within Africa Analysis.” We motivate this reformulation with five shortcomings largely drawn from the 2015 findings of the African Gerome Variation Project, notably: limitations in the conception of space, an African dummy in genetic diversity, linearity in migratory patterns, migratory origins and underpinnings of genetic diversity in Africa. Ashraf and Galor have concluded that cross-country differences in development can be explained by genetic diversity in a Kuznets or inverted U-shaped pattern. Our results from an exclusive African perspective partially confirm the underlying hypothesis in a contemporary context, but not in the historical analysis. From a historical context, the nexus is U-shaped for migratory distance, mobility index and predicted diversity while for the contemporary analysis; it is hump shaped for ancestry-adjusted predicted diversity. Hence from a within-Africa comparative standpoint, poverty is not in the African gene. |
| 448. | Kodila-Tedika, Asongu & S A South African Journal of Economics, 2017. Abstract | Links | BibTeX | Tags: Africa; Genetic diversity; Comparative economic development @article{Asongu_445, author = {Asongu & S A Kodila-Tedika}, url = {http://onlinelibrary.wiley.com/doi/10.1111/saje.12165/full}, doi = {10.1111/saje.12165/full}, year = {2017}, date = {2017-07-07}, journal = {South African Journal of Economics}, abstract = {A 2015 World Bank report on attainment of Millennium Development Goals concludes that the number of extremely poor has dropped substantially in all regions with the exception of Sub-Saharan Africa. We assess if poverty is in the African gene by revisiting the findings of Ashraf and Galor and reformulating the “Out of Africa Hypothesis” into a “Genetic Diversity Hypothesis” for a “Within Africa Analysis.” We motivate this reformulation with five shortcomings largely drawn from the 2015 findings of the African Gerome Variation Project, notably: limitations in the conception of space, an African dummy in genetic diversity, linearity in migratory patterns, migratory origins and underpinnings of genetic diversity in Africa. Ashraf and Galor have concluded that cross-country differences in development can be explained by genetic diversity in a Kuznets or inverted U-shaped pattern. Our results from an exclusive African perspective partially confirm the underlying hypothesis in a contemporary context, but not in the historical analysis. From a historical context, the nexus is U-shaped for migratory distance, mobility index and predicted diversity while for the contemporary analysis; it is hump shaped for ancestry-adjusted predicted diversity. Hence from a within-Africa comparative standpoint, poverty is not in the African gene.}, keywords = {Africa; Genetic diversity; Comparative economic development}, pubstate = {published}, tppubtype = {article} } A 2015 World Bank report on attainment of Millennium Development Goals concludes that the number of extremely poor has dropped substantially in all regions with the exception of Sub-Saharan Africa. We assess if poverty is in the African gene by revisiting the findings of Ashraf and Galor and reformulating the “Out of Africa Hypothesis” into a “Genetic Diversity Hypothesis” for a “Within Africa Analysis.” We motivate this reformulation with five shortcomings largely drawn from the 2015 findings of the African Gerome Variation Project, notably: limitations in the conception of space, an African dummy in genetic diversity, linearity in migratory patterns, migratory origins and underpinnings of genetic diversity in Africa. Ashraf and Galor have concluded that cross-country differences in development can be explained by genetic diversity in a Kuznets or inverted U-shaped pattern. Our results from an exclusive African perspective partially confirm the underlying hypothesis in a contemporary context, but not in the historical analysis. From a historical context, the nexus is U-shaped for migratory distance, mobility index and predicted diversity while for the contemporary analysis; it is hump shaped for ancestry-adjusted predicted diversity. Hence from a within-Africa comparative standpoint, poverty is not in the African gene. |
| 449. | Asongu, Nicholas Biekpe Simplice A 2017. Abstract | Links | BibTeX | Tags: Financial access; Information asymmetry; ICT @unpublished{Asongu_446, author = {Nicholas Biekpe Simplice A. Asongu}, url = {http://www.afridev.org/RePEc/agd/agd-wpaper/ICT-Information-Asymmetry-and-Market-Power-in-the-African-Banking-Industry.pdf}, year = {2017}, date = {2017-06-27}, abstract = {This study assesses how market power in the African banking industry is affected by the complementarity between information sharing offices and information and communication technology (ICT). The empirical evidence is based on a panel of 162 banks consisting of 42 countries for the period 2001-2011. Four estimation techniques are employed, namely: (i) instrumental variable Fixed effects to control for the unobserved heterogeneity; (ii) Tobit regressions to control for the limited range in the dependent variable; and (iii) Instrumental Quantile Regressions (QR) to account for initial levels of market power. Whereas results from Fixed effects and Tobit regressions are not significant, with QR: (i) the interaction between internet penetration and public credit registries reduces market power in the 75th quartile and (ii) the interaction between mobile phone penetration and private credit bureaus increases market power in the top quintiles. Fortunately, the positive net effects are associated with negative marginal effects from the interaction between private credit bureaus and mobile phone penetration. This implies that mobile phones could complement private credit bureaus to decrease market power when certain thresholds of mobile phone penetration are attained. These thresholds are computed and discussed.}, keywords = {Financial access; Information asymmetry; ICT}, pubstate = {published}, tppubtype = {unpublished} } This study assesses how market power in the African banking industry is affected by the complementarity between information sharing offices and information and communication technology (ICT). The empirical evidence is based on a panel of 162 banks consisting of 42 countries for the period 2001-2011. Four estimation techniques are employed, namely: (i) instrumental variable Fixed effects to control for the unobserved heterogeneity; (ii) Tobit regressions to control for the limited range in the dependent variable; and (iii) Instrumental Quantile Regressions (QR) to account for initial levels of market power. Whereas results from Fixed effects and Tobit regressions are not significant, with QR: (i) the interaction between internet penetration and public credit registries reduces market power in the 75th quartile and (ii) the interaction between mobile phone penetration and private credit bureaus increases market power in the top quintiles. Fortunately, the positive net effects are associated with negative marginal effects from the interaction between private credit bureaus and mobile phone penetration. This implies that mobile phones could complement private credit bureaus to decrease market power when certain thresholds of mobile phone penetration are attained. These thresholds are computed and discussed. |
| 450. | Asongu, Nicholas Biekpe Simplice A 2017. Abstract | Links | BibTeX | Tags: Entrepreneurship; the Mobile Phone; Knowledge Diffusion; Sub-Saharan Africa @unpublished{Asongu_447, author = {Nicholas Biekpe Simplice A. Asongu}, url = {http://www.afridev.org/RePEc/agd/agd-wpaper/Mobile-Phone-Innovation-and-Entrepreneurship-in-Sub-Saharan-Africa.pdf}, year = {2017}, date = {2017-06-27}, abstract = {This study assesses how knowledge diffusion modulates the effect of the mobile phone on entrepreneurship in Sub-Saharan Africa with data for the period 2000-2012.The empirical evidence is based on interactive Generalised Method of Moments in which mobile phones are interacted with three knowledge diffusion variables, namely: education, internet penetration and scientific output. Ten variables of entrepreneurship are used. The following three main findings are established. First, the net effects from interacting mobile phones with the internet and scientific publications are negative whereas the corresponding net impact from the interaction between mobile phones and education is positive on the cost of doing business. Second, the mobile phone interacts with education (the internet) to have a positive (negative) net effect on the time needed to construct a warehouse whereas, the corresponding interaction with the internet yields a net negative effect on the time to enforce a contract. Third, there is a positive net effect from the interaction of mobile phones with education on the time to start a business. Given the construction of the education variable, the positive net effects from education are consistent with corresponding negative net effects from the other knowledge diffusion variables. The main policy implication is that mobile phone innovation (by means of internet penetration, scientific output and quality education) decreases constraints of entrepreneurship. Suggestions on how to boost these knowledge diffusion channels are discussed. Other practical and theoretical implications are also covered. To the best our knowledge, this is the first inquiry to assess the relevance of mobile phone innovation in entrepreneurship in Sub-Saharan Africa.}, keywords = {Entrepreneurship; the Mobile Phone; Knowledge Diffusion; Sub-Saharan Africa}, pubstate = {published}, tppubtype = {unpublished} } This study assesses how knowledge diffusion modulates the effect of the mobile phone on entrepreneurship in Sub-Saharan Africa with data for the period 2000-2012.The empirical evidence is based on interactive Generalised Method of Moments in which mobile phones are interacted with three knowledge diffusion variables, namely: education, internet penetration and scientific output. Ten variables of entrepreneurship are used. The following three main findings are established. First, the net effects from interacting mobile phones with the internet and scientific publications are negative whereas the corresponding net impact from the interaction between mobile phones and education is positive on the cost of doing business. Second, the mobile phone interacts with education (the internet) to have a positive (negative) net effect on the time needed to construct a warehouse whereas, the corresponding interaction with the internet yields a net negative effect on the time to enforce a contract. Third, there is a positive net effect from the interaction of mobile phones with education on the time to start a business. Given the construction of the education variable, the positive net effects from education are consistent with corresponding negative net effects from the other knowledge diffusion variables. The main policy implication is that mobile phone innovation (by means of internet penetration, scientific output and quality education) decreases constraints of entrepreneurship. Suggestions on how to boost these knowledge diffusion channels are discussed. Other practical and theoretical implications are also covered. To the best our knowledge, this is the first inquiry to assess the relevance of mobile phone innovation in entrepreneurship in Sub-Saharan Africa. |