Abstract
An original cross-sectional dataset referring to a medium-sized Italian university is implemented in order to analyze the determinants of scientific research production at individual level. The dataset includes 942 permanent researchers of various scientific sectors for a 3-year time-span (2008–2010). Three different indicators—based on the number of publications and/or citations—are considered as response variables. The corresponding distributions are highly skewed and display an excess of zero-valued observations. In this setting, the goodness-of-fit of several Poisson mixture regression models are explored by assuming an extensive set of explanatory variables. As to the personal observable characteristics of the researchers, the results emphasize the age effect and the gender productivity gap—as previously documented by existing studies. Analogously, the analysis confirms that productivity is strongly affected by the publication and citation practices adopted in different scientific disciplines. The empirical evidence on the connection between teaching and research activities suggests that no univocal substitution or complementarity thesis can be claimed: a major teaching load does not affect the odds to be a non-active researcher and does not significantly reduce the number of publications for active researchers. In addition, new evidence emerges on the effect of researchers administrative tasks—which seem to be negatively related with researcher’s productivity—and on the composition of departments. Researchers’ productivity is apparently enhanced by operating in department filled with more administrative and technical staff, and it is not significantly affected by the composition of the department in terms of senior/junior researchers.
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Abramo, G., D’Angelo, C. A., & Caprasecca, A. (2009). Gender differences in research productivity: A bibliometric analysis of the Italian academic system. Scientometrics, 79, 517–539.
Allison, P. D., & Long, J. S. (1990). Departmental effects on scientific productivity. American Sociological Review, 55, 469–478.
Allison, P. D., & Stewart, J. A. (1974). Productivity differences among scientists: Evidence for accumulative advantage. American Sociological Review, 39, 596–606.
Anania, G., & Caruso, A. (2013). Two simple new bibliometric indexes to better evaluate research in disciplines where publications typically receive less citations. Scientometrics, 96, 617–631.
Barabesi, L., & Pratelli, L. (2014). Discussion of “On simulation and properties of the stable law” by L. Devroye and L: James. Statistical Methods & Applications. doi:10.1007/s10260-014-0263-x.
Bayer, A. E., & Dutton, J. E. (1977). Career age and research professional activities of academic scientists. Journal of Higher Education, 48, 259–282.
Böhning, D., Dietz, E., Schlattmann, P., Mendonça, L., & Kirchner, U. (1999). The zero-inflated Poisson model and the decayed, missing and filled teeth index in dental epidemiology. Journal of the Royal Statistical Society Series A, 162, 195–209.
Bonaccorsi, A., & Daraio, C. (2003). Age effects in scientific productivity. The case of the Italian National Research Council (CNR). Scientometrics, 58, 49–90.
Burrell, Q. L. (2005). The use of the generalized Waring process in modelling informetric data. Scientometrics, 64, 247–270.
Burrell, Q. L., & Fenton, M. R. (1993). Yes, the GIGP really does work – and is workable! Journal of the American Society for Information Science, 44, 61–69.
Cainelli, G., de Felice, A., Lamonarca, M., & Zoboli, R. (2006). The publications of Italian economists in ECONLIT: Quantitative assessment and implications for research evaluation. Economia Politica, 23, 385–423.
Carayol, N., & Matt, M. (2004). Does research organization influence academic production? Laboratory level evidence from a large European university. Research Policy, 33, 1081–1102.
Carayol, N., & Matt, M. (2006). Individual and collective determinants of academic scientists’ productivity. Information Economics and Policy, 18, 55–72.
Chambers, J. M., & Hastie, T. J. (Eds.). (1992). Statistical Models in S. London: Chapman & Hall.
Cole, J. R., & Cole, S. (1973). Social Stratification in Science. Chicago: University of Chicago Press.
Cole, J. R., & Zuckerman, H. (1984). The productivity puzzle: Persistence and change in patterns of publication of men and women scientists. In M. W. Steinkempt & M. L. Maehr (Eds.), Advances in Motivation and Achievement (pp. 217–258). Conn.: JAI Press, Greenwich.
Dalrymple, M. L., Hudson, I. L., & Ford, R. P. K. (2003). Finite mixture, zero-inflated Poisson and hurdle models with application to SIDS. Computational Statistics & Data Analysis, 41, 491–504.
David, P. (1994). Positive feedbacks and research productivity in science: Reopening another black box. In O. Grandstrand (Ed.), Economics and Technology (pp. 65–85). Amsterdam: Elsevier.
Defazio, D., Lockett, A., & Wright, M. (2009). Funding incentives, collaborative dynamics and scientific productivity: Evidence from the EU framework program. Research Policy, 38, 293–305.
Diamond, A. M. (1984). An economic-model of the life-cycle research productivity of scientists. Scientometrics, 6, 189–196.
Diamond, A. M. (1986). The life-cycle research productivity of mathematicians and scientists. The Journal of Gerontology, 41, 520–525.
Fabel, O., Hein, M., & Hofmeister, R. (2008). Research productivity in business economics: An investigation of Austrian, German and Swiss universities. German Economic Review, 9, 506–531.
Fox, M. F. (1992). Research, teaching and publication productivity: Mutuality versus competition in academia. Sociology of Education, 65, 293–305.
Fox, M. F. (2005). Gender, family characteristics, and publication productivity among scientists. Social Studies of Science, 35, 131–150.
Fox, M. F., Fonseca, C., & Bao, J. (2011). Work and family conflict in academic science: Patterns and predictors among women and men in research universities. Social Studies of Science, 41, 715–735.
Hall, D. B. (2000). Zero-inflated Poisson and binomial regression with random effects: A case study. Biometrics, 56, 1030–1039.
Hicks, D. (2004). The four literatures of social science. In F. H. Moed, W. Glaenzel, & U. Schmoch (Eds.), Handbook of Quantitative Science and Technology Research (pp. 473–496). Dordrecht, Boston and London: Kluwer Academic Publishers.
Hirsch, J. E. (2005). An index to quantify an individual’s scientific research output. Proceedings of the National Academy of Sciences of the United States of America, 102, 16569–16572.
Iglesias, J. E., & Pecharroman, C. (2007). Scaling the h-index for different scientific ISI fields. Scientometrics, 73, 303–320.
Irwin, J. O. (1968). The generalized Waring distribution applied to accident theory. Journal of the Royal Statistical Society. Series A (General), 131, 205–225.
Johnson, N. L., Kemp, A. W., & Kotz, S. (2005). Univariate discrete distributions (3rd ed.). New York: Wiley.
Kelchtermans, K., & Veugelers, R. (2011). The great divide in scientific productivity: Why the average scientist does not exist. Industrial and Corporate Change, 20, 295–336.
Kossi, Y., Lesueur, J. Y., & Sabatier, M. (2013). Publish or teach? The role of the scientific environment on academics multitasking. Groupe d’Analyse et de Théorie Économique Lyon-St Étienne, GATE WP 1315.
Lambert, D. (1992). Zero-inflated Poisson regression, with an application to defects in manufacturing. Technometrics, 34, 1–17.
Leahey, E. (2006). Gender differences in productivity: Research specialization as a missing link. Gender & Society, 20, 754–780.
Levin, S., & Stephan, P. E. (1991). Research productivity over the life cycle: Evidence for academic scientists. American Economic Review, 81, 114–132.
Levin, S., & Stephan, P. E. (1998). Gender differences in the rewards to publishing in academe: Science in the 1970s. Sex Roles, 38, 1041–1064.
Lissoni, F., Mairesse, J., Montobbio, F., & Pezzoni, M. (2011). Scientific productivity and academic promotion: A study on French and Italian physicists. Industrial and Corporate Change, 20, 253–294.
Lotka, A. J. (1926). The frequency distribution of scientific productivity. Journal of the Washington Academy of Science, 16, 317–323.
Mairesse J., Pezzoni M. (2013). Does gender affect scientific productivity? A critical review of the empirical evidence and a panel data econometric analysis for French physicists. Presented to AFSE Meeting, Aix en Provence, 26 June 2013.
Mairesse, J., Turner, L. (2006). Measurement and explanation of the intensity of co-publication in scientific research: An analysis at the laboratory level. In: Antonelli, C., Foray, D., Hall, B. H., Steinmueller, W. E. (Eds), New Frontiers in the Economics of Innovation and New Technology: Essays in Honour of Paul A. David. Edward Elgar, Cheltenham and Northampton, pp 255–295.
Marcheselli, M., Baccini, A., & Barabesi, L. (2008). Parameter estimation for the discrete stable family. Communications in statistics: Theory and methods, 37, 815–830.
Martin, B. R., & Irvine, J. (1983). Assessing basic research: Some partial indicators of scientific progress in radio astronomy. Research Policy, 12, 61–90.
Merton, R. (1968). The Matthew effect in science. Science, 159, 56–63.
Minami, M., Lennert-Cody, C. E., Gao, W., & Román-Verdesoto, M. (2007). Modeling shark bycatch: The zero-inflated negative binomial regression model with smoothing. Fisheries Research, 84, 210–221.
Mullahy, J. (1986). Specification and testing of some modified count data models. Journal of Econometrics, 33, 341–365.
Pezzoni, M., Sterzi, V., & Lissoni, F. (2012). Career progress in centralized academic systems: Social capital and institutions in France and Italy. Research Policy, 41, 704–719.
R Core Team (2012). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, from http://www.R-project.org/.
Rao, I. K. R. (1980). The Distribution of Scientific Productivity and Social Change. Journal of the American Society for Information Science, 31, 111–122.
Rathbun, S. L., & Fei, S. (2006). A spatial zero-inflated Poisson regression model for oak regeneration. Environmental and Ecological Statistics, 13, 409–426.
Rigby, R. A., Stasinopoulos, D. M., & Akantziliotou, C. (2008). A framework for modelling overdispersed count data, including the Poisson-shifted generalized inverse Gaussian distribution. Computational Statistics and Data Analysis, 53, 381–393.
Rivera-Huerta, R., Dutrénit, G., Ekboir, J. M., Sampedro, J. L., & Vera-Cruz, A. O. (2011). Do linkages between farmers and academic researchers influence researcher productivity? The Mexican case. Research Policy, 40, 932–942.
Rodríguez-Avi, J., Conde-Sánchez, A., Sáez-Castillo, A. J., Olmo-Jiménez, M. J., & Martínez-Rodríguez, A. M. (2009). A generalized Waring regression model for count data. Computational Statistics and Data Analysis, 53, 3717–3725.
Rose, C. E., Martin, S. W., Wannemuehler, K. A., & Plikaytis, B. D. (2006). On the use of zero-inflated and hurdle models for modeling vaccine adverse event count data. Journal of Biopharmaceutical Statistics, 16, 463–481.
Schubert, A., & Glänzel, W. (1984). A dynamic Look at a class of skew distributions. A model with scientometric applications. Scientometrics, 6, 149–167.
Schubert, A., & Telcs, A. (1989). Estimation of the publication potential in 50 U.S. states and in the District of Columbia based on the frequency distribution of scientific productivity. Journal of the American Society for Information Science, 40, 291–297.
Sibuya, M. (1979). Generalized hypergeometric, digamma and trigamma distributions. Annals of the Institute of Statistical Mathematics, 31, 373–390.
Sichel, H. S. (1985). A bibliometric distribution which really works. Journal of the American Society for Information Science, 36, 314–321.
Stephan, P. E. (1996). The economics of science. Journal of Economic Literature, 34, 1199–1235.
Stephan, P. E. (2012). How Economics Shapes Science. Cambridge, Mass: Harvard University Press.
Taylor, S. W., Fender, B. F., & Burke, K. G. (2006). Unraveling the academic productivity of economists: The opportunity costs of teaching and service. Southern Economic Journal, 72, 846–859.
van Arensbergen, P., van der Weijden, I., & van den Besselaar, P. (2012). Gender differences in scientific productivity: A persisting phenomenon? Scientometrics, 93, 857–868.
van Leeuwen, T. N., Visser, M. S., Moed, H. F., Nederhof, T. J., & van Raan, A. F. J. (2003). The Holy Grail of science policy: Exploring and combining bibliometric tools in search of scientific excellence. Scientometrics, 57, 257–280.
Venables, W. N., & Ripley, B. D. (2002). Modern Applied Statistics with S. New York: Springer-Verlag.
Wallner, B., Fieder, M., & Iber, K. (2003). Age profile, personnel costs and scientific productivity at the University of Vienna. Scientometrics, 58, 143–153.
Wang, D., Song, C., & Barabási, A. L. (2013). Quantifying long-term scientific impact. Science, 342, 127–132.
Weiss, Y., & Lillard, L. A. (1982). Output variability, academic labor contracts, and waiting times for promotion. Research in Labor Economics, 5, 157–188.
Wooton, R. (2013). A simple, generalizable method for measuring individual research productivity and its use in the long-term analysis of departmental performance, including between-country comparisons. Health Research Policy and Systems, 11, 1–14.
Xie, Y., & Shauman, K. A. (2003). Women in science: Career processes and outcomes. Cambridge: Harvard University Press.
Zeileis, A., Kleiber, C., & Jackman, S. (2008). Regression models for count data in R. Journal of Statistical Software, 27, 1–25.
Zhang, X., Lei, Y., Cai, D., & Liu, F. (2012). Predicting tree recruitment with negative binomial mixture models. Forest Ecology and Management, 270, 209–215.
Zuckerman, H. A., & Merton, R. K. (1972). Age, aging, and age structure in science. In M. R. Riley, M. Johnson, & A. Foner (Eds.), A sociology of age stratification: Aging and society (pp. 292–356). New York: Russell Sage Foundation.
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We would like to thank Sonia Boldrini from the Evaluation Committee of the University of Siena for her valuable assistance in data harvesting and database building. In addition, we would like to express our gratitude to two anonymous referees for their comments which have led to a truly improved version of the paper.
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Baccini, A., Barabesi, L., Cioni, M. et al. Crossing the hurdle: the determinants of individual scientific performance. Scientometrics 101, 2035–2062 (2014). https://doi.org/10.1007/s11192-014-1395-3
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DOI: https://doi.org/10.1007/s11192-014-1395-3