本文以Stock and Watson (1998)的方法為基礎，建立一個兩步驟的「擴散指標」預測模型，並應用於經濟成長率的預測。除了依循Stock and Watson (1998)的作法作，我們也將變依其特性區分為商品市場變數，貨幣市場變數與勞動市場變數，再分別針對各市場變數估計其擴散指標，然後根據這些指標進行預測。實證結果顯示，「擴散指標」預測模型具有相當好的預測績效，也於國內一些經濟單位所作的預測，因此可以作為未來總體經濟預測上的另一種選擇。

In this paper, we construct a two-step model for forecasting Taiwan’s economic growth rates based on the “diffusion indexes” method proposed by Stock and Watson (1998). In addition to Stock and Watson’s original approach, we also classify the macro-economic variables into three makers and compute their respective diffusion indexes. A forecasting model it then constructed using these market-specific indexes. Our results show that, based on various evaluation criteria, the diffusion-index-based forecasting models usually perform better than those reported by other forecasting agencies in Taiwan. Hence, the models proposed here are good alternatives in macroeconomic forecasting.