如何通过高频数据对债基进行归因？：债券基金专题分析

1. Report Industry Investment Rating No industry investment rating is provided in the report. 2. Core Views of the Report - The Campisi model, a classic attribution framework in the fixed - income field, decomposes the total return of a pure - bond fund into four effects: income, treasury, spread, and selection effects, helping to evaluate a fund manager's abilities such as duration management and credit mining [6]. - The net - based Campisi model (RBA) constructs seven risk factors through factor regression, with advantages in high - frequency tracking and dynamic adaptability, capable of capturing strategy adjustments and market environment changes [2][80]. - The net - based Campisi model has strong explanatory power for fixed - income funds. From early 2025 to August 22, 2025, the adjusted R - squared generally exceeded 0.6, indicating that the model can explain most of the income sources [2][80]. - The model can identify strategy characteristics. For example, in 2025, interest - rate bond funds generally extended their durations, and credit bond funds shifted to a diversified strategy due to narrowing spreads. "Fixed - income +" funds balanced risks and returns through diversified rating allocations and maintained high exposure to option - containing assets [2][80][81]. 3. Summary by Relevant Catalogs 3.1 Performance Attribution of Fixed - Income Funds - The core value of fixed - income fund performance attribution lies in evaluating management capabilities, guiding investment decisions, and optimizing risk management. Its practical significance benefits investors, managers, and regulatory agencies [5]. 3.2 Net - based Campisi Model 3.2.1 Campisi Model Principle - The Campisi model decomposes the total return of a pure - bond fund into four effects: income, treasury, spread, and selection effects, helping to assess a fund manager's abilities in various aspects [6]. - The income effect is the coupon income during bond holding, independent of market interest rate fluctuations. The treasury effect measures the impact of changes in risk - free interest rates on bond prices, and the spread effect reflects the impact of changes in credit spreads on bond prices. The selection effect reflects the fund manager's active management ability [7][8][13]. - The Campisi model can be divided into the portfolio - based (PBA) and net - based (RBA) models. PBA has high decomposition accuracy but low timeliness, while RBA has high - frequency tracking and dynamic adaptability [14]. 3.2.2 Model Construction and Factor Selection - The net - based Campisi model decomposes bond returns into seven factors: interest - rate level, term structure, convexity, credit spread, rating spread, convertible bond, and equity factors [18]. - Each factor has its own construction method and reflects different aspects of a fund's risk exposure and strategy preference. For example, the interest - rate level factor reflects the impact of the parallel shift of the interest - rate curve on bond portfolio returns, and the convertible bond factor captures the income contribution of convertible bond assets [20][34]. 3.2.3 Factor Performance and Processing - Since January 2020, the convertible bond and equity factors have fluctuated greatly, while non - option - containing factors have shown an upward trend in the long - term. The interest - rate level, term structure, credit spread, and rating spread factors have stable long - term trends, and the convexity factor has the smallest fluctuation [39]. - There are certain correlations among the factors. For example, the convertible bond factor and the equity factor have a strong positive correlation, while the interest - rate level factor has a negative correlation with the convertible bond and equity factors [40]. 3.3 Bond Fund Performance Evaluation Empirical Analysis 3.3.1 Pure - Bond Fund Attribution Analysis - From early 2025 to August 22, 2025, the adjusted R - squared of interest - rate bond funds and credit bond funds was generally high, indicating that the model can explain most of the fund income [45]. - Compared with 2024, in 2025, interest - rate bond funds generally extended their durations and increased exposure to convexity factors. Credit bond funds also extended their durations but to a lesser extent, and their investment strategies became more diversified [45][50][52]. - Short - term bond funds have a higher average exposure to the term structure factor, reflecting their preference for short - term bonds. Medium - and long - term bond funds have more diversified investment directions in credit bonds [55]. 3.3.2 Characteristics of Top - Ranked Pure - Bond Funds in Alpha in 2025 - Top - ranked medium - and long - term interest - rate bond funds in Alpha generally have higher exposure to the interest - rate level factor and negative exposure to the term structure factor. Alpha, mainly from the selection effect, has a relatively small impact on their performance [58]. - Top - ranked medium - and long - term credit bond funds in Alpha have negative exposure to the rating spread factor, indicating a tendency to reduce credit risk exposure. Alpha also has a relatively small impact on their performance [61]. 3.3.3 "Fixed - Income +" Fund Attribution Analysis - From early 2025 to August 22, 2025, the adjusted R - squared of "fixed - income +" funds was generally high, and most of them had positive Alpha, indicating strong overall active management ability [63]. - In a low - interest - rate environment, "fixed - income +" funds balance risks and returns through diversified rating allocations and maintain high exposure to option - containing assets [67]. 3.3.4 Characteristics of "Fixed - Income +" Funds with Strong Active Management Ability in 2025 - Top - ranked "fixed - income +" funds in Alpha rely more on the fund manager's active management ability, and Alpha has a greater impact on their performance [76]. - Top - ranked "fixed - income +" funds in the convertible bond factor also mostly have strong active management ability [78]. 3.4 Investment Analysis Opinions - The net - based Campisi model provides a systematic tool for fixed - income funds, helping investors screen and allocate funds with stable strategies and strong active management abilities [80][81].