Joint Forecasts of U.S. Marital Fertility, Nuptiality, Births, and Marriages Using Time Series Models

Abstract

This article presents a new approach to forecasting U.S. marital fertility, nuptiality, births, and marriages. The analysis represents a wedding of demographic and statistical time series in models amenable to Box-Jenkins techniques of model identification, estimation, diagnosis, and forecasting. The models demonstrate the advantages in this approach in forecasting both rates and events as opposed to the common practice of simply forecasting events. Using the best models of indexes of fertility and nuptiality, forecasts of births and first marriages are made for the U.S. for the years 1983–2000. Analyses of these forecasts are made with discussions of their demographic realism in terms of their forecast confidence intervals.

Key Words:

• Index of fertility
• Index of nuptiality
• ARIMA models
• Transfer function models
• Vector ARMA models