Tempo-Adjusted Period Parity Progression Measures, Fertility Postponement and Completed Cohort Fertility

Abstract

4 Parity Progression Measures under Alternative Postponement Scenarios 4.1 Extrapolation of fertility postponement to future periods 4.2 Conditional parity progression probabilities 4.3 Conditional parity progression ratios 4.4 Conditional cohort mean age at birth 5 Using the Model: Measuring Period Fertility and Completing Cohort Fertility 5.1 Parity progression measures for measuring period fertility 5.2 Completing the fertility of cohorts 6 Empirical Implementation Notes References A Appendix

Tempo and the TFR

“…This implicit construal of bias/distortion-viewing period measures as erroneous indicators of real cohort values-is fairly common in the literature on tempo adjustment (Bongaarts 2008;Kohler and Ortega 2002a;Schoen 2004;Smallwood 2002b;Sobotka 2003;van Imhoff 2001;van Imhoff and Keilman 2000).…”

“…Terminology varies, with some sources using the term bias alone or interchangeably with distortion (Bongaarts 2002;Bongaarts and Feeney 1998;Kohler and Ortega 2002b;Kohler and Philipov 2001;van Imhoff and Keilman 2000;Land 2001, 2002) and other, particularly more recent, sources referring exclusively to distortion (Bongaarts 1999(Bongaarts , 2008Bongaarts and Feeney 2000;Frejka et al 2008;Frejka and Ross 2001;Kohler et al 2002;Kohler and Ortega 2002a;Schoen 2004;Sobotka 2004a). The two terms are used interchangeably in the recent fertility literature, mean the same thing, and are considered synonymous in the present article.…”

Completing incomplete cohort fertility schedules

“…While quite a few researchers are skeptical about the usefulness of these adjusted period measures, due to their assumptions regarding the shape of the fertility schedules and/or due to their fluctuating and occasionally absurd values (e.g., Kim and Schoen 2000;Li and Wu 2003;Schoen 2004;Van Imhoff and Keilman 2000), some researchers have compared them with the CTFR (e.g., Kohler and Ortega 2002;Ryder 1990;Schoen 2004;Smallwood 2002;Sobotka 2003;Van Imhoff and Keilman 2000), explicitly or implicitly regarding these period indicators as forecasts of the completed fertility for cohorts who have not finished childbearing. In these studies, two popular ways of relating period and cohort fertility measures were adopted, namely, to compare the CTFR for cohort c with the period estimate at time p at which the cohort reaches its mean age at birth (i.e., c+MAB c = p), or to compare the estimate at time p with the CTFR for women who reach the mean age at birth in that year (i.e., p − MAB p = c).…”

Poland: Fertility decline as a response to profound societal and labour market changes?

“…Indeed, the Kohler-Ortega (2002) adjusted total fertility index (adjPATFR) shows that if the shift of childbearing to higher ages had been taken into account, fertility would have been higher by 0.2-0.3 children per woman for the whole period after 1993. This would mean a total fertility of 1.54 in 2002, as indicated by adjPATFR, which is, however, still low and represents a considerable decline when compared to 1990, when the adjPATFR was 2.08.…”

“…(2006) and Bolesławski (1993). NOTE: The Adjusted PATFR index was computed according to the formula proposed by Kohler and Ortega (2002) for first and second births. It is constructed from the schedule age and parity-specific birth probabilities, which are adjusted to remove distortions caused by changes in the timing of childbearing.…”