基差改善VIX回落，市场情绪升持续温修复

• The report introduces the Cinda-VIX volatility index, which reflects investors' expectations of future volatility in the options market. The index is structured to capture volatility across different time horizons, providing insights into market sentiment and risk expectations[62][61][64] - The methodology for constructing the Cinda-VIX index is based on overseas practices and adjusted to fit the characteristics of China's options market. The calculation is detailed in the research series "Exploring Market Sentiment Embedded in the Options Market"[62][61] - As of October 24, 2025, the 30-day Cinda-VIX values for major indices are: 19.23 for SSE 50, 19.32 for CSI 300, 27.76 for CSI 500, and 24.15 for CSI 1000[62][63][64] - The report also introduces the Cinda-SKEW index, which measures the skewness of implied volatility across different strike prices of options. This index helps investors understand market expectations regarding the distribution of future returns and potential tail risks[66][67][61] - The SKEW index is particularly useful for identifying market concerns about extreme negative events, often referred to as "black swan" risks. A SKEW value above 100 indicates heightened investor concern about significant downside risks[67][66] - As of October 24, 2025, the SKEW values for major indices are: 101.75 for SSE 50, 103.69 for CSI 300, 102.25 for CSI 500, and 102.63 for CSI 1000[67][68][66]