Intervention analysis with application to the wholesale price index in korea

Abstract

The price level in Korea has been affected by a few great interventions which were due to the government policies and the foreign factors. From Jan. 1965 to Dec. 1980, four big shocks could be clearly observed on the Wholesale Price Index (W.P.I.), which were caused by the rises in oil price and changes in the foreign exchange rate. The purpose of this thesis is to investigate the nature of the shocks and their causalities to the general price level. The Intervention Analysis technique was used to see the effects of the shocks to the W.P.I., and the modified identification method of the Multiple Input Intervention model was suggested. It was found that the effects of the first oil price hike in Dec. 1973 and the change in the foreign exchange rate in Jan. 1980 to the W.P.I. were similar. The first foreign exchange shock had an oscillating effect on the W.P.I. with a second tide of foreign effects lagged by three months. In addition, the monthly change rate of the W.P.I. was 0.71\% on the average in the pre-intervention period and it followed the MA(1) process with alternatively damping weights.