Contributions to mathematical demography
This is a continuous research effort, with some focus on extending Ryder’s translation formulae for the relationship between period and cohort fertility indicators, to non-repeatable events.
R. Gill and N. Keilman. 1990. On the estimation of multidimensional demographic models with population registration data. Mathematical Population Studies, 2, 119-143.
N. Keilman. 1994. Translation formulae for non-repeatable events. Population Studies 48(2)1994, 341-357.
N. Keilman. 1993. Du fondement et de l'usage des taux. Population 48, 423-427. Also published in English as "Period fertility indices – A comment" in Population: An English Selection 6, 1994, 111-115.
D. Courgeau, N. Keilman, et E. Lelièvre. 1994. Estimation d'un quotient a l'aide de données agrégées. Population 49, 229-232.
N. Keilman and E. van Imhoff. 1995. Cohort quantum as a function of time-dependent period quantum for non-repeatable events. Population Studies 49, 347-352.
H. Urdal and N. Keilman. 1996. Barnløshet i fremtiden - en formell demografisk analyse ("Childlessness in the future - a formal demographic analysis"). Økonomisk Analyse 2/1996, 29-38.
N. Keilman. 1998. Female dominance. Pp. 215-228 in A. Kuijsten, H. de Gans and H. de Feijter (eds.) The joy of demography ….. and other disciplines: Essays in honour of Dirk van de Kaa. Amsterdam: Thela - Thesis Publ., 1998.
E. van Imhoff and N. Keilman. 2000. On the quantum and tempo of fertility: Comment. Population and Development Review 26, 549-553. A more detailed version was published under the same title as NIDI Working Paper 1999/2. The Hague: Netherlands Interdisciplinary Demographic Institute. Internet http://www.nidi.nl/public/ nidi_wp_1999_2.pdf .
N. Keilman. 2001. La traslazione demografica: dalla prospettiva di periodo a quella per generazione e viceversa. Pp 439-461 G. Caselli, J. Vallin, e G. Wunsch Demografia: La dinamica delle popolazioni. Roma: Carocci.
N. Keilman. 2001. La translation démographique: des indicateurs du moment aux indicateurs de génération et réciproquement. Pp. 359-378 dans G. Caselli, J. Vallin, et G. Wunsch Démographie: analyse et synthèse. Vol. I La dynamique des populations. Paris: Editions de l’Institut National d’Etudes Démographiques. Also appeared as Memorandum no. 06/2000, Department of Economics, University of Oslo. Internet http://www.sv.uio.no/sosoek/memo/ memopdf/memo0600.pdf.