Helmi Hammami | ESC RENNES SCHOOL OF BUSINESS (original) (raw)
Papers by Helmi Hammami
The Energy Journal, 2021
We explore the drivers of impact for energy economics research based on an analysis of citations ... more We explore the drivers of impact for energy economics research based on an analysis of citations generated by The Energy Journal articles. The focus is on non-topic generators of impact. Our regression analysis shows that these non-topic measures can explain a substantial proportion (about 20%) of variation in future citations. We apply these findings, integrated with prior research on effective economics writing style, to recommend how energy economics articles should be written to increase their impact. These recommendations center particularly around the importance of initial article information provided to the reader and article structure.
Journal of Behavioral and Experimental Finance, 2020
This study investigates the aptitudes of the cash-based and accrual-based accounting data for pre... more This study investigates the aptitudes of the cash-based and accrual-based accounting data for predicting future cash flows from operations in the French context. In addition, our paper aims to investigate the effect of the economic crisis on the prediction of future cash flow. The sample consists of 61 non-financial French listed companies, using annual data over the period 1999–2016. The study found that, regardless of the period, the model based on the operating cash flows combined with disaggregate accruals has a stronger explanatory power for predicting future operating cash flows, compared to both earnings and operating cash flows combined with the aggregate accruals models. Moreover, our results show that the aggregation of earnings falsifies the contribution of each accrual item and, as a result, the decomposition of earnings into cash flows and disaggregate accrual enables a much more accurate explanation of future operating cash flows.
Journal of Information Science, 39 (2) p 211–224, Apr 2013
"Starting from an ontology of a targeted financial domain corresponding to transaction, performan... more "Starting from an ontology of a targeted financial domain corresponding to transaction, performance and management change news, relevant
segments of text containing at least a domain keyword are extracted. The linguistic pattern of each segment is automatically generated
to serve initially as a learning model. Each pattern is composed of named entities, keywords and articulation words. Some generic
named entities like organizations, persons, locations, dates and grammatical annotations are generated by an automatic tool. During
the learning step, each relevant segment is manually annotated with respect to the targeted entities (roles) structuring an event of the
ontology. Information extraction is processed by associating a role with a specific entity. By alignment of generic entities to specific entities,
some strings of a text are automatically annotated. An original learning approach is presented. Experiments with the management
change event showed how recognition rates are improved by using different generalization tools."
Business Systems Review, 1 (1), 2012., 2012
The study aims to empirically investigate the predictive ability of reported cash flows versus ... more The study aims to empirically investigate the predictive ability of reported cash
flows versus earnings to predict future cash flows in a market situated in a high growth rate
economy such as Qatar. The sample of the study consists of companies on the Doha
Securities Market (Qatar Exchange) for the period 2004-09. Qatar is a very interesting
context to explore especially after the quick reputation it is gaining at the international scene.
We provide evidence on the ability of earnings and cash flow measures to forecast one ...
International Research Journal of Applied Finance, Vol III (3), p 409 - 422, Mar 2012
"Index funds are widely accepted as the best option for investors seeking diversification. Howeve... more "Index funds are widely accepted as the best option for investors seeking diversification. However
when the cost of investing is high these benefits can be wiped out. We examine such a possibility
in Qatar, a small but emerging financial market where the cost of investing in index funds is
high compared to western countries. Using a new approach to diversification we show that index
funds in small financial markets are only useful in times of low expectations. In times of high
expectations investors are better of buying a small number of stocks directly from the market."
Qatar Foundation …, Jan 1, 2010
International Research Journal of Applied Finance, Jan 2012
This study investigates the residuals of discretionary accruals of listed firms in the Qatar Exc... more This study investigates the residuals of discretionary accruals of listed firms in the Qatar
Exchange and the U.S. stock market for the period 2004-2009. Our findings show that
discretionary accruals of listed firms from the Qatar Exchange are significantly greater than
those from the U. S. stock market. Qatar has proven its reserves of natural gas to be about
14% of the world total and third largest in the world. And about 20% of the Qatar Exchange
is owned by NYSE Euronext. From the empirical results by three different accrual models,
we find that Qatari firms in three industries (service, manufacturing and insurance) tend to
manage earnings positively compared with those in the U.S. stock market. Our findings
suggest that IFRS adoption and FIFO inventory method under inflationary environment by
the Qatari firms resulted in greater residuals from all three accrual models than the U.S. stock
market listed firms.
La stratégie de pair trading est une stratégie d'arbitrage statistique assez répandue. Elle est ... more La stratégie de pair trading est une stratégie d'arbitrage statistique assez répandue.
Elle est basée sur l'arbitrage d'un retour à la moyenne de la série de corrélation
d'une paire d'actions ou les résidus d'un modèle de cointégration. Les problématiques
liées à cette strategie résident dans la dé nition de ce type de caractéristique
(plusieurs dé nitions existent dans la littérature) et la détermination de la meilleure
méthode de séléction. Cet article propose un protocole de test pour comparer les diff
érentes dé nitions en utilisant des séries simulées de diérents types. Les meilleures
méthodes sont appliquées à des données réelles. On montre qu'ajouter une bonne
méthode de séléction des séries "mean reverting" permet d'augmenter les performances
de la stratégie en réduisant son temps d'exposition aux marchés, sa volatilité
et en augmentant son ratio de sharpe.
Education, Business and Society: Contemporary Middle Eastern Issues 3 (1), 48-62 , 2010
The purpose of this paper is to investigate how business students and business professionals in... more The purpose of this paper is to investigate how business students and business
professionals in Qatar perceive the accountancy profession. Design/methodology/approach–
The paper designs a survey based on Osgood semantic differential theory of attitude
assessment (30 bipolar pairs). The survey is administrated to 400 respondents. Factor
analysis reduces variables to five and analysis of variance is employed to study the main
differences between groups.
Advances in Accounting, incorporating Advances in International Accounting 25 (2), 255-265 , 2009
"This study sets out to examine empirically the determinants of voluntary disclosure in the annua... more "This study sets out to examine empirically the determinants of voluntary disclosure in the annual reports of
25 listed firms of Doha Securities Market (DSM) in Qatar forming approximately 86% of the total firms
incorporated in DSM. It also reports the results of the association between company-specific characteristics
and voluntary disclosure of the sample companies. A disclosure checklist consisting of 44 voluntary items of
information is developed and statistical analysis is performed using multiple regression analysis. The
findings indicate that age, size, complexity, and assets-in-place are significant and other variable profitability
is insignificant in explaining the level of voluntary disclosure. However, this paper has contributed to the
academic literature that firms in the Middle East provide voluntary corporate information which builds a
confidence to the investors in general and Qatar in particular."
Afro-Asian Journal of Finance and Accounting 1 (4), 353-366 , 2009
"Accounting teaching in developing countries is facing serious challenges due to the increasing... more "Accounting teaching in developing countries is facing serious challenges due to
the increasing number of students. Accounting expert systems as a teaching method can
help manage this flow. The objective of this study was to test the effectiveness of expert
systems as a teaching method compared to regular professor-based teaching. Knowledge
acquisition was tested over two dimensions:"
The Energy Journal, 2021
We explore the drivers of impact for energy economics research based on an analysis of citations ... more We explore the drivers of impact for energy economics research based on an analysis of citations generated by The Energy Journal articles. The focus is on non-topic generators of impact. Our regression analysis shows that these non-topic measures can explain a substantial proportion (about 20%) of variation in future citations. We apply these findings, integrated with prior research on effective economics writing style, to recommend how energy economics articles should be written to increase their impact. These recommendations center particularly around the importance of initial article information provided to the reader and article structure.
Journal of Behavioral and Experimental Finance, 2020
This study investigates the aptitudes of the cash-based and accrual-based accounting data for pre... more This study investigates the aptitudes of the cash-based and accrual-based accounting data for predicting future cash flows from operations in the French context. In addition, our paper aims to investigate the effect of the economic crisis on the prediction of future cash flow. The sample consists of 61 non-financial French listed companies, using annual data over the period 1999–2016. The study found that, regardless of the period, the model based on the operating cash flows combined with disaggregate accruals has a stronger explanatory power for predicting future operating cash flows, compared to both earnings and operating cash flows combined with the aggregate accruals models. Moreover, our results show that the aggregation of earnings falsifies the contribution of each accrual item and, as a result, the decomposition of earnings into cash flows and disaggregate accrual enables a much more accurate explanation of future operating cash flows.
Journal of Information Science, 39 (2) p 211–224, Apr 2013
"Starting from an ontology of a targeted financial domain corresponding to transaction, performan... more "Starting from an ontology of a targeted financial domain corresponding to transaction, performance and management change news, relevant
segments of text containing at least a domain keyword are extracted. The linguistic pattern of each segment is automatically generated
to serve initially as a learning model. Each pattern is composed of named entities, keywords and articulation words. Some generic
named entities like organizations, persons, locations, dates and grammatical annotations are generated by an automatic tool. During
the learning step, each relevant segment is manually annotated with respect to the targeted entities (roles) structuring an event of the
ontology. Information extraction is processed by associating a role with a specific entity. By alignment of generic entities to specific entities,
some strings of a text are automatically annotated. An original learning approach is presented. Experiments with the management
change event showed how recognition rates are improved by using different generalization tools."
Business Systems Review, 1 (1), 2012., 2012
The study aims to empirically investigate the predictive ability of reported cash flows versus ... more The study aims to empirically investigate the predictive ability of reported cash
flows versus earnings to predict future cash flows in a market situated in a high growth rate
economy such as Qatar. The sample of the study consists of companies on the Doha
Securities Market (Qatar Exchange) for the period 2004-09. Qatar is a very interesting
context to explore especially after the quick reputation it is gaining at the international scene.
We provide evidence on the ability of earnings and cash flow measures to forecast one ...
International Research Journal of Applied Finance, Vol III (3), p 409 - 422, Mar 2012
"Index funds are widely accepted as the best option for investors seeking diversification. Howeve... more "Index funds are widely accepted as the best option for investors seeking diversification. However
when the cost of investing is high these benefits can be wiped out. We examine such a possibility
in Qatar, a small but emerging financial market where the cost of investing in index funds is
high compared to western countries. Using a new approach to diversification we show that index
funds in small financial markets are only useful in times of low expectations. In times of high
expectations investors are better of buying a small number of stocks directly from the market."
Qatar Foundation …, Jan 1, 2010
International Research Journal of Applied Finance, Jan 2012
This study investigates the residuals of discretionary accruals of listed firms in the Qatar Exc... more This study investigates the residuals of discretionary accruals of listed firms in the Qatar
Exchange and the U.S. stock market for the period 2004-2009. Our findings show that
discretionary accruals of listed firms from the Qatar Exchange are significantly greater than
those from the U. S. stock market. Qatar has proven its reserves of natural gas to be about
14% of the world total and third largest in the world. And about 20% of the Qatar Exchange
is owned by NYSE Euronext. From the empirical results by three different accrual models,
we find that Qatari firms in three industries (service, manufacturing and insurance) tend to
manage earnings positively compared with those in the U.S. stock market. Our findings
suggest that IFRS adoption and FIFO inventory method under inflationary environment by
the Qatari firms resulted in greater residuals from all three accrual models than the U.S. stock
market listed firms.
La stratégie de pair trading est une stratégie d'arbitrage statistique assez répandue. Elle est ... more La stratégie de pair trading est une stratégie d'arbitrage statistique assez répandue.
Elle est basée sur l'arbitrage d'un retour à la moyenne de la série de corrélation
d'une paire d'actions ou les résidus d'un modèle de cointégration. Les problématiques
liées à cette strategie résident dans la dé nition de ce type de caractéristique
(plusieurs dé nitions existent dans la littérature) et la détermination de la meilleure
méthode de séléction. Cet article propose un protocole de test pour comparer les diff
érentes dé nitions en utilisant des séries simulées de diérents types. Les meilleures
méthodes sont appliquées à des données réelles. On montre qu'ajouter une bonne
méthode de séléction des séries "mean reverting" permet d'augmenter les performances
de la stratégie en réduisant son temps d'exposition aux marchés, sa volatilité
et en augmentant son ratio de sharpe.
Education, Business and Society: Contemporary Middle Eastern Issues 3 (1), 48-62 , 2010
The purpose of this paper is to investigate how business students and business professionals in... more The purpose of this paper is to investigate how business students and business
professionals in Qatar perceive the accountancy profession. Design/methodology/approach–
The paper designs a survey based on Osgood semantic differential theory of attitude
assessment (30 bipolar pairs). The survey is administrated to 400 respondents. Factor
analysis reduces variables to five and analysis of variance is employed to study the main
differences between groups.
Advances in Accounting, incorporating Advances in International Accounting 25 (2), 255-265 , 2009
"This study sets out to examine empirically the determinants of voluntary disclosure in the annua... more "This study sets out to examine empirically the determinants of voluntary disclosure in the annual reports of
25 listed firms of Doha Securities Market (DSM) in Qatar forming approximately 86% of the total firms
incorporated in DSM. It also reports the results of the association between company-specific characteristics
and voluntary disclosure of the sample companies. A disclosure checklist consisting of 44 voluntary items of
information is developed and statistical analysis is performed using multiple regression analysis. The
findings indicate that age, size, complexity, and assets-in-place are significant and other variable profitability
is insignificant in explaining the level of voluntary disclosure. However, this paper has contributed to the
academic literature that firms in the Middle East provide voluntary corporate information which builds a
confidence to the investors in general and Qatar in particular."
Afro-Asian Journal of Finance and Accounting 1 (4), 353-366 , 2009
"Accounting teaching in developing countries is facing serious challenges due to the increasing... more "Accounting teaching in developing countries is facing serious challenges due to
the increasing number of students. Accounting expert systems as a teaching method can
help manage this flow. The objective of this study was to test the effectiveness of expert
systems as a teaching method compared to regular professor-based teaching. Knowledge
acquisition was tested over two dimensions:"