Indonesian Stock Market Crisis Observation with Spectral and Composite Index

The paper discusses the employment of the index composed from the dynamical tree of correlations among stock prices both with the popularly used standard (conventional) composite one. The spectral index focus on the dynamics of the correlation coefficients among stock prices while composite index is the dynamical aggregate of the whole stocks traded in the market. Some advantages is conjectured by incorporating both indexes to the historical data of Indonesian Stock Market data. Both are shown potentially useful for detecting the crisis as well as the general stock-prices relations on fundamental issues, generally social, economic, and political situations on which the Indonesian stock market is influenced.