AN ANALYSIS OF VOLATILITY STRUCTURE AND REGIME SWITCHING OF BIST CITY INDICES

This study attempts to determine volatility and regime switching structure of BIST C？ty Indices over 2012-2017 period by using daily closing values. Three asymmetrical (EGARCH, TGARCH and PARCH) as well as two symmetrical (ARCH and GARCH) models were tested to reveal any asymmetrical conditions in comparing the volatilities and regime switching structure of XSADA, XSANT, XSANK, XSBAL, XSBUR, XSDNZ, XSIST, XSIZM, XSKAY, XSKOC, XSKON and XSTKR. For each model, three lagged values were calculated. TIC coefficients were used in comparing the models. The analyses of the volatility persistency reveal that XSKOC index is the most volatile and XSKAY index is the most stable according to remaining indices. The results of daily volatilities reveal that XSANT is the most volatile index while XSKOC is the most stable index. As a result of the analysis in order to determine regime structure of indices, two regimes were detected for all (12) indices which were taken into consideration. According to findings, the indices generally prefer to stay in higher regime if they are in the high regime and they tend to shift from low regime to the high regime if they are in low regime. XSBUR Index offers significant opportunities to the investors while staying 62.06 days in the high regime period whereas XSADA index was determined as the shortest high regime-staying period through only 9.41 days. XSIZM Index was determined as the worst index based on its duration (7.18 days) for staying in low regime. On the other hand, the XSKAY Index was detected as the shortest-staying index in low regime and fastest index escape from the decline trend