The Study of ICT Sector's Network Efficiency in Korea: Influence of Import and Sector Difference

The technology network studies derive the network relationship according to the trade of intermediate goods between sectors and classify the sectors in the efficient position. Technical network studies use both models that include or exclude import. Differences can arise in the Korean market, where the proportion of intermediate goods is high. Thus, this study analyzes the influence of import on the technology network. Also, Korea's industry is divided into ICT and non-ICT sectors to clarify the differences. Difference in difference (DiD) panel analysis is used to separate the level of influence and the change over time in multi-period analysis. This study found that (1) the network efficiency is high and the constraint is not changed by import. Higher network efficiency means higher total added value. This study has implications for verifying the effect of import on the network impact level not considered in the technical system network studies. (2) The network efficiency of the non-ICT sector was higher than that of the ICT sector, and the network constraint was not different. This can judge to be relatively inefficient in Korea's ICT sector in the network for the full economy. (3) In order to clarify the numerical change caused by industrial development, it is necessary to eliminate the change caused by the passage of time. As an alternative, this study solved this problem by using multi-period DID panel analysis. This study may be helpful to government investment and policy makers as well as corporate policy makers.