- The GAN_GRU factor is based on the GAN_GRU model, which utilizes a Generative Adversarial Network (GAN) for processing volume-price time series features and then uses a GRU model for time series feature encoding to derive the stock selection factor[4][13][14] - The GAN_GRU model includes two GRU layers (GRU(128, 128)) followed by an MLP (256, 64, 64), with the final output prediction return (pRet) used as the stock selection factor[22] - The GAN model consists of a generator and a discriminator. The generator aims to generate data that appears real, while the discriminator aims to distinguish between real and generated data. The generator's loss function is $L_{G} = -\mathbb{E}_{z\sim P_{z}(z)}[\log(D(G(z)))]$[23][24][25] - The discriminator's loss function is $L_{D} = -\mathbb{E}_{x\sim P_{data}(x)}[\log D(x)] - \mathbb{E}_{z\sim P_{z}(z)}[\log(1-D(G(z)))]$[27][28][29] - The GAN_GRU model's training process involves alternating training of the generator and discriminator until convergence[30] - The GAN_GRU factor's performance from January 2019 to September 2025 shows an IC mean of 0.1136, an annualized excess return of 22.58%, and a recent IC of 0.1053 as of September 28, 2025[41][42] - The GAN_GRU factor's IC mean for the past year is 0.0982, with the highest IC values in the coal, building materials, social services, non-bank finance, and food & beverage industries[42][44] - The top-performing long portfolios in September 2025, based on the GAN_GRU factor, include sectors like building materials, steel, social services, coal, and non-bank finance, with excess returns of 5.78%, 5.13%, 1.91%, 1.55%, and 1.21%, respectively[45] - Over the past year, the top-performing long portfolios based on the GAN_GRU factor include home appliances, building materials, food & beverage, utilities, and textiles & apparel, with average monthly excess returns of 5.04%, 4.96%, 3.92%, 3.53%, and 3.10%, respectively[46] - The top stocks in each industry based on the GAN_GRU factor as of September 28, 2025, include companies like Baolaite, Yutaiwei-U, Cangge Mining, Tuowei Information, Hengtong Co., Angang Co., and others[49][50]

Quantitative Models and Construction Methods 1. Model Name: Weekly Rebalancing AI-Enhanced CSI 500 Wide Constraint Portfolio - **Model Construction Idea**: This model aims to enhance the CSI 500 index performance by leveraging AI-based factors while applying wide constraints on portfolio construction [72][73] - **Model Construction Process**: - The model uses deep learning factors (e.g., multi-granularity model with 10-day labels) as the basis for stock selection [72] - Constraints include: - Stock weight: 1% - Industry weight: 1% - Market cap weight: 0.3 - Turnover rate constraint: 0.3 - The optimization objective is to maximize expected returns, represented by the formula: $$ max \sum \mu_{i}w_{i} $$ where \( w_{i} \) is the weight of stock \( i \) in the portfolio, and \( \mu_{i} \) is the expected excess return of stock \( i \) [73][74] - **Model Evaluation**: The model demonstrates moderate performance under wide constraints, with cumulative excess returns shown over time [75][77] 2. Model Name: Weekly Rebalancing AI-Enhanced CSI 500 Strict Constraint Portfolio - **Model Construction Idea**: Similar to the wide constraint model but applies stricter constraints to control risk and enhance robustness [72][73] - **Model Construction Process**: - Constraints include: - Stock weight: 1% - Industry weight: 1% - Market cap weight: 0.1 - Additional constraints: - Market cap squared: 0.1 - ROE: 0.3 - SUE: 0.3 - Volatility: 0.3 - Component stock constraint: 0.8 - Optimization objective remains the same as the wide constraint model [73][74] - **Model Evaluation**: The stricter constraints result in a more stable performance, with cumulative excess returns displayed over time [76][80] 3. Model Name: Weekly Rebalancing AI-Enhanced CSI 1000 Wide Constraint Portfolio - **Model Construction Idea**: This model targets the CSI 1000 index, applying wide constraints while leveraging AI-based factors for enhanced returns [72][73] - **Model Construction Process**: - Constraints are similar to the CSI 500 wide constraint model, with a focus on smaller-cap stocks [73] - **Model Evaluation**: The model shows significant cumulative excess returns, particularly in recent years [79][86] 4. Model Name: Weekly Rebalancing AI-Enhanced CSI 1000 Strict Constraint Portfolio - **Model Construction Idea**: Similar to the wide constraint model but applies stricter constraints to manage risk and improve consistency [72][73] - **Model Construction Process**: - Constraints are similar to the CSI 500 strict constraint model, tailored for the CSI 1000 index [73] - **Model Evaluation**: The model demonstrates strong performance under strict constraints, with cumulative excess returns highlighted [85][87] --- Model Backtesting Results 1. Weekly Rebalancing AI-Enhanced CSI 500 Wide Constraint Portfolio - **Weekly Excess Return**: -1.36% (last week), -3.85% (September), 0.94% (YTD 2025) [13][78] - **Weekly Win Rate**: 23/39 weeks [13] 2. Weekly Rebalancing AI-Enhanced CSI 500 Strict Constraint Portfolio - **Weekly Excess Return**: -1.35% (last week), -1.33% (September), 3.70% (YTD 2025) [13][81] - **Weekly Win Rate**: 24/39 weeks [13] 3. Weekly Rebalancing AI-Enhanced CSI 1000 Wide Constraint Portfolio - **Weekly Excess Return**: 0.40% (last week), 0.42% (September), 9.15% (YTD 2025) [13][83] - **Weekly Win Rate**: 26/39 weeks [13] 4. Weekly Rebalancing AI-Enhanced CSI 1000 Strict Constraint Portfolio - **Weekly Excess Return**: -0.19% (last week), 0.67% (September), 14.01% (YTD 2025) [13][90] - **Weekly Win Rate**: 25/39 weeks [13] --- Quantitative Factors and Construction Methods 1. Factor Name: Intraday Skewness Factor - **Factor Construction Idea**: Captures the skewness of intraday stock returns to identify potential outperformers [6][8] - **Factor Construction Process**: Referenced in the report "Stock Selection Factor Series Research (19)" [13] - **Factor Evaluation**: Demonstrates strong performance with IC values of 0.027 (historical) and 0.042 (2025) [9][10] 2. Factor Name: Downside Volatility Proportion Factor - **Factor Construction Idea**: Measures the proportion of downside volatility in realized volatility to assess risk-adjusted returns [6][8] - **Factor Construction Process**: Referenced in the report "Stock Selection Factor Series Research (25)" [18][20] - **Factor Evaluation**: Shows moderate performance with IC values of 0.025 (historical) and 0.036 (2025) [9][10] 3. Factor Name: Post-Open Buying Intensity Factor - **Factor Construction Idea**: Quantifies the intensity of buying activity after market open to identify short-term momentum [6][8] - **Factor Construction Process**: Referenced in the report "Stock Selection Factor Series Research (64)" [22][26] - **Factor Evaluation**: Displays stable performance with IC values of 0.035 (historical) and 0.030 (2025) [9][10] 4. Factor Name: Deep Learning Factor (Improved GRU(50,2)+NN(10)) - **Factor Construction Idea**: Utilizes a gated recurrent unit (GRU) and neural network (NN) architecture to predict stock returns [6][8] - **Factor Construction Process**: Combines GRU with NN to capture temporal dependencies in high-frequency data [61][62] - **Factor Evaluation**: Strong performance with IC values of 0.066 (historical) and 0.050 (2025) [12][61] --- Factor Backtesting Results 1. Intraday Skewness Factor - **IC**: 0.027 (historical), 0.042 (2025) [9][10] - **Multi-Long-Short Return**: 3.82% (September), 16.22% (YTD 2025) [9][10] 2. Downside Volatility Proportion Factor - **IC**: 0.025 (historical), 0.036 (2025) [9][10] - **Multi-Long-Short Return**: 2.86% (September), 13.58% (YTD 2025) [9][10] 3. Post-Open Buying Intensity Factor - **IC**: 0.035 (historical), 0.030 (2025) [9][10] - **Multi-Long-Short Return**: 0.65% (September), 11.29% (YTD 2025) [9][10] 4. Deep Learning Factor (Improved GRU(50,2)+NN(10)) - **IC**: 0.066 (historical), 0.050 (2025) [12][61] - **Multi-Long-Short Return**: 2.13% (September), 7.40% (YTD 2025) [12][61]

Quantitative Factors and Models Summary Quantitative Factors and Construction Methods 1. **Factor Name**: DL_EM_Dynamic - **Construction Idea**: Extract intrinsic stock attributes from public fund holdings using matrix decomposition, and combine these attributes with LSTM-generated factor representations to create dynamic market state factors[19][21]. - **Construction Process**: - Matrix decomposition is applied to fund-stock investment networks to derive intrinsic matrices for funds and stocks[19]. - Static intrinsic attributes are updated semi-annually using fund reports and transformed into dynamic attributes by calculating their similarity to current market preferences[19]. - These dynamic attributes are combined with LSTM outputs and fed into an MLP model to enhance performance[19]. - The factor is used to construct a CSI 1000 enhanced index portfolio with constraints on tracking error (5%), industry exposure (±0.02), style exposure (±0.5), and individual stock weight (3%). Weekly rebalancing is applied, and transaction costs are set at 0.2% for both sides[21]. 2. **Factor Name**: Meta_RiskControl - **Construction Idea**: Incorporate factor exposure control into deep learning models to mitigate drawdowns during rapid style factor changes[26]. - **Construction Process**: - Multiply model outputs by corresponding stock factor exposures and include this in the loss function[26]. - Add penalties for style deviations and style momentum to the IC-based loss function[26]. - Use an ALSTM model with style inputs as the base model and integrate it with a meta-incremental learning framework for dynamic market adaptation[26]. - Construct enhanced portfolios for CSI 300, CSI 500, and CSI 1000 indices with constraints on market cap deviation (±0.5), industry deviation (±0.02), and individual stock weight (5x benchmark weight). Weekly rebalancing and 0.2% transaction costs are applied[29]. 3. **Factor Name**: Meta_Master - **Construction Idea**: Leverage market-guided stock transformer models (MASTER) and deep risk models to capture market states and improve factor performance[36]. - **Construction Process**: - Incorporate market state vectors derived from recent price-volume data of CSI 300, CSI 500, and CSI 1000 indices into the MASTER model[36]. - Construct 120 new features representing market states based on the styles of recently best-performing stocks[36]. - Replace the loss function with weighted MSE to enhance long-side prediction accuracy and use online meta-incremental learning for periodic model updates[36]. - Construct enhanced portfolios for CSI 300, CSI 500, and CSI 1000 indices with constraints on market cap deviation (±0.5), industry deviation (±0.02), and individual stock weight (5x benchmark weight). Weekly rebalancing and 0.2% transaction costs are applied[38]. 4. **Factor Name**: Deep Learning Convertible Bond Factor - **Construction Idea**: Address the diminishing excess returns of traditional convertible bond strategies by using GRU deep neural networks to model the complex nonlinear pricing logic of convertible bonds[50]. - **Construction Process**: - Introduce convertible bond-specific time-series factors into the GRU model[50]. - Combine cross-sectional bond attributes with GRU outputs to predict future returns, significantly improving model performance[50]. --- Factor Backtesting Results 1. **DL_EM_Dynamic Factor** - **RankIC**: 11.3% (July 2025, CSI 1000)[7][10] - **Excess Return**: 1.3% (July 2025, CSI 1000); 11% YTD (2025)[7][10] - **Annualized Return**: 29.7% (since 2019)[23] - **Annualized Excess Return**: 23.4% (since 2019)[23] - **IR**: 2.03 (since 2019)[23] - **Max Drawdown**: -10.1% (since 2019)[23] 2. **Meta_RiskControl Factor** - **RankIC**: 15.5% (July 2025, All A-shares)[7][13] - **Excess Return**: - CSI 300: 1.9% (July 2025); 6.4% YTD (2025)[31] - CSI 500: 1.4% (July 2025); 4.4% YTD (2025)[33] - CSI 1000: 1.3% (July 2025); 9.3% YTD (2025)[35] - **Annualized Return**: - CSI 300: 20.1% (since 2019)[31] - CSI 500: 26.1% (since 2019)[33] - CSI 1000: 34.1% (since 2019)[35] - **Annualized Excess Return**: - CSI 300: 15.0% (since 2019)[31] - CSI 500: 19.2% (since 2019)[33] - CSI 1000: 27.0% (since 2019)[35] - **IR**: - CSI 300: 1.58 (since 2019)[31] - CSI 500: 1.97 (since 2019)[33] - CSI 1000: 2.36 (since 2019)[35] - **Max Drawdown**: - CSI 300: -5.8% (since 2019)[31] - CSI 500: -9.3% (since 2019)[33] - CSI 1000: -10.2% (since 2019)[35] 3. **Meta_Master Factor** - **RankIC**: 18.9% (July 2025, All A-shares)[7][16] - **Excess Return**: - CSI 300: 2.0% (July 2025); 7.9% YTD (2025)[39] - CSI 500: 1.6% (July 2025); 5.5% YTD (2025)[45] - CSI 1000: 1.4% (July 2025); 8.1% YTD (2025)[47] - **Annualized Return**: - CSI 300: 22.0% (since 2019)[39] - CSI 500: 23.8% (since 2019)[45] - CSI 1000: 30.7% (since 2019)[47] - **Annualized Excess Return**: - CSI 300: 17.5% (since 2019)[39] - CSI 500: 18.2% (since 2019)[45] - CSI 1000: 25.2% (since 2019)[47] - **IR**: - CSI 300: 2.09 (since 2019)[39] - CSI 500: 1.9 (since 2019)[45] - CSI 1000: 2.33 (since 2019)[47] - **Max Drawdown**: - CSI 300: -7.2% (since 2019)[39] - CSI 500: -5.8% (since 2019)[45] - CSI 1000: -8.8% (since 2019)[47] 4. **Deep Learning Convertible Bond Factor** - **Absolute Return**: - July 2025: 5.8% (equity-biased), 3.8% (balanced), 3.3% (debt-biased)[52] - Annualized (since 2021): 13.2% (equity-biased), 11.8% (balanced), 12.7% (debt-biased)[52] - **Excess Return**: - July 2025: 1.5% (equity-biased), -0.4% (balanced), -0.9% (debt-biased)[55] - Annualized (since 2021): 5.8% (equity-biased), 4.0% (balanced), 4.4% (debt-biased)[55]

Quantitative Models and Construction Methods - **Model Name**: DecompGRU **Model Construction Idea**: The model improves the GRU baseline by introducing two simple de-mean modules to enhance the interaction between temporal and cross-sectional information[14] **Model Construction Process**: 1. The DecompGRU model architecture is based on GRU with added de-mean modules for trend decomposition[14] 2. Two versions of the model are trained using different loss functions: IC and weighted MSE[14] 3. The IC-based model and MSE-based model are used to score stocks, and the top 200 stocks are selected for portfolio construction[8][14] **Evaluation**: The model effectively captures temporal and cross-sectional interactions, leading to improved stock selection performance[14] Model Backtesting Results - **DecompGRU Model**: - Cumulative absolute return: 24.54% - Excess return relative to WIND All A equal-weight index: 9.80% - Maximum drawdown: 10.08% - Weekly win rate: 72.22% - Monthly win rate: 100%[10] - **ETF Rotation Portfolio (Based on DecompGRU Scores)**: - Cumulative absolute return: 12.97% - Excess return relative to WIND ETF index: 8.65% - Maximum drawdown: 6.16% - Weekly win rate: 68.42% - Monthly win rate: 75%[12] Quantitative Factors and Construction Methods - **Factor Name**: Total Heat Indicator **Factor Construction Idea**: The indicator aggregates stock-level attention metrics (views, favorites, clicks) to represent market sentiment at broader levels (indices, industries, concepts)[17][18] **Factor Construction Process**: 1. Calculate the sum of views, favorites, and clicks for each stock[18] 2. Normalize the sum as a percentage of the total market activity on the same day[18] 3. Multiply the normalized value by 10,000 to derive the final indicator, with a range of [0, 10,000][18] **Evaluation**: The factor serves as a proxy for sentiment-driven mispricing, particularly effective at the stock level[18] Factor Backtesting Results - **Broad Index Heat Rotation Strategy**: - Annualized return since 2017: 8.74% - Maximum drawdown: 23.5% - 2025 YTD return: 18.8% - Benchmark return: 17.1%[27] - **Concept Heat BOTTOM Portfolio**: - Annualized return: 15.71% - Maximum drawdown: 28.89% - 2025 YTD return: 27%[44] Additional Observations - **Broad Index Heat Changes**: - Largest increase: CSI 500 (+10.21%) - Largest decrease: CSI 2000 (-6.02%)[27][29] - **Industry Heat Changes**: - Top 5 positive changes: Building Materials (+83.5%), Building Decoration, Social Services, Steel, Food & Beverage - Top 5 negative changes: Light Manufacturing (-32.5%), Textile & Apparel, Automotive, Real Estate, Utilities[38] - **Concept Heat Changes**: - Top 5 concepts: Dairy (+233.5%), Football (+194.9%), NMN (+115), Short Drama Games (+113.6%), Rent-Sale Rights (+109.6)[39][47][48]

Quantitative Models and Construction Methods 1. Model Name: GRU(50,2)+NN(10) Factor - **Model Construction Idea**: This factor leverages a deep learning architecture combining Gated Recurrent Units (GRU) and Neural Networks (NN) to capture high-frequency trading patterns and predict stock returns[4][55] - **Model Construction Process**: - The GRU(50,2) component processes sequential high-frequency data with 50 units and 2 layers - The NN(10) component is a fully connected neural network with 10 neurons in the output layer - The model is trained on historical high-frequency data to predict stock returns, optimizing for multi-class classification or regression tasks[4][55] - **Model Evaluation**: Demonstrates robust performance in capturing high-frequency trading signals and generating stable returns[4][55] 2. Model Name: Multi-Granularity Model (5-Day Label) - **Model Construction Idea**: This model uses multi-granularity data to predict stock returns over a 5-day horizon, leveraging bidirectional AGRU (Attention-based GRU) for feature extraction[57][60] - **Model Construction Process**: - Input data is segmented into multiple granularities (e.g., daily, intraday) - Bidirectional AGRU is applied to extract temporal features from the data - A 5-day label is used as the prediction target, and the model is trained to optimize for this horizon[57][60] - **Model Evaluation**: Effective in capturing medium-term trading patterns and generating consistent returns[57][60] 3. Model Name: Multi-Granularity Model (10-Day Label) - **Model Construction Idea**: Similar to the 5-day label model, this version extends the prediction horizon to 10 days, using bidirectional AGRU for feature extraction[60][65] - **Model Construction Process**: - Multi-granularity data is processed with bidirectional AGRU - A 10-day label is used as the prediction target, and the model is trained to optimize for this extended horizon[60][65] - **Model Evaluation**: Provides a longer-term perspective on trading patterns, with slightly lower returns compared to the 5-day model but still effective[60][65] --- Model Backtesting Results GRU(50,2)+NN(10) Factor - **IC**: Historical: 0.066, 2025: 0.039[4][55] - **e^(-RankMAE)**: Historical: 0.336, 2025: 0.334[4][55] - **Long-Short Return**: Weekly: 0.70%, June: 3.58%, 2025 YTD: 19.78%[4][55] - **Long-Only Excess Return**: Weekly: -0.30%, June: 0.92%, 2025 YTD: -1.06%[4][55] Multi-Granularity Model (5-Day Label) - **IC**: Historical: 0.081, 2025: 0.070[57][60] - **e^(-RankMAE)**: Historical: 0.344, 2025: 0.343[57][60] - **Long-Short Return**: Weekly: 1.56%, June: 5.97%, 2025 YTD: 35.45%[57][60] - **Long-Only Excess Return**: Weekly: 0.40%, June: 2.16%, 2025 YTD: 11.87%[57][60] Multi-Granularity Model (10-Day Label) - **IC**: Historical: 0.074, 2025: 0.065[60][65] - **e^(-RankMAE)**: Historical: 0.342, 2025: 0.343[60][65] - **Long-Short Return**: Weekly: 1.66%, June: 5.76%, 2025 YTD: 33.44%[60][65] - **Long-Only Excess Return**: Weekly: 0.71%, June: 2.06%, 2025 YTD: 11.11%[60][65] --- Quantitative Factors and Construction Methods 1. Factor Name: Intraday Skewness Factor - **Factor Construction Idea**: Measures the skewness of intraday returns to capture asymmetry in price movements[4][10] - **Factor Construction Process**: - Calculate intraday returns for each stock - Compute the skewness of these returns using the formula: $ Skewness = \frac{E[(X - \mu)^3]}{\sigma^3} $ where $X$ is the return, $\mu$ is the mean, and $\sigma$ is the standard deviation[4][10] - **Factor Evaluation**: Effective in identifying stocks with asymmetric return distributions, though performance varies across periods[4][10] 2. Factor Name: Downside Volatility Ratio - **Factor Construction Idea**: Focuses on the proportion of downside volatility relative to total volatility to capture risk-averse behavior[4][14] - **Factor Construction Process**: - Calculate downside volatility as the standard deviation of negative returns - Compute the ratio of downside volatility to total volatility[4][14] - **Factor Evaluation**: Useful for identifying stocks with higher downside risk, though returns are sensitive to market conditions[4][14] 3. Factor Name: Opening Buy Intensity - **Factor Construction Idea**: Measures the intensity of buy orders during the opening period to capture early trading sentiment[4][17] - **Factor Construction Process**: - Aggregate buy orders in the first 30 minutes of trading - Normalize by total trading volume during the same period[4][17] - **Factor Evaluation**: Captures short-term sentiment effectively, though performance is volatile[4][17] --- Factor Backtesting Results Intraday Skewness Factor - **IC**: Historical: 0.027, 2025: 0.047[4][10] - **e^(-RankMAE)**: Historical: 0.324, 2025: 0.330[4][10] - **Long-Short Return**: Weekly: -0.51%, June: 1.48%, 2025 YTD: 14.73%[4][10] - **Long-Only Excess Return**: Weekly: -0.03%, June: 0.18%, 2025 YTD: 2.59%[4][10] Downside Volatility Ratio - **IC**: Historical: 0.025, 2025: 0.046[4][14] - **e^(-RankMAE)**: Historical: 0.324, 2025: 0.328[4][14] - **Long-Short Return**: Weekly: -0.04%, June: 1.86%, 2025 YTD: 12.84%[4][14] - **Long-Only Excess Return**: Weekly: 0.09%, June: 0.50%, 2025 YTD: 1.07%[4][14] Opening Buy Intensity - **IC**: Historical: 0.031, 2025: 0.028[4][17] - **e^(-RankMAE)**: Historical: 0.322, 2025: 0.322[4][17] - **Long-Short Return**: Weekly: 0.77%, June: 1.85%, 2025 YTD: 11.44%[4][17] - **Long-Only Excess Return**: Weekly: 0.04%, June: 0.61%, 2025 YTD: 5.91%[4][17]

Quantitative Models and Construction Methods Quantitative Factors and Their Construction 1. **Factor Name**: Intraday Skewness Factor **Construction Idea**: Captures the skewness of intraday stock returns to identify potential return asymmetry[3][6] **Construction Process**: Referenced in the report "Stock Selection Factor Series Research (19) - High-Frequency Factors on Stock Return Distribution Characteristics"[11] **Evaluation**: Demonstrates mixed performance with positive returns in some periods but underperformance in others[3][6] 2. **Factor Name**: Downside Volatility Proportion Factor **Construction Idea**: Measures the proportion of downside volatility in intraday price movements to assess risk[3][6] **Construction Process**: Referenced in the report "Stock Selection Factor Series Research (25) - High-Frequency Factors on Realized Volatility Decomposition"[16] **Evaluation**: Shows consistent positive returns in certain periods but limited robustness in others[3][6] 3. **Factor Name**: Post-Open Buy Intention Proportion Factor **Construction Idea**: Quantifies the proportion of buy orders after market open to gauge investor sentiment[3][6] **Construction Process**: Referenced in the report "Stock Selection Factor Series Research (64) - Low-Frequency Applications of High-Frequency Data Using Intuitive Logic and Machine Learning"[20] **Evaluation**: Exhibits moderate performance with occasional strong returns[3][6] 4. **Factor Name**: Post-Open Buy Intention Intensity Factor **Construction Idea**: Measures the intensity of buy orders after market open to reflect market momentum[3][6] **Construction Process**: Referenced in the report "Stock Selection Factor Series Research (64) - Low-Frequency Applications of High-Frequency Data Using Intuitive Logic and Machine Learning"[24] **Evaluation**: Performance is inconsistent, with periods of underperformance[3][6] 5. **Factor Name**: Post-Open Large Order Net Buy Proportion Factor **Construction Idea**: Tracks the proportion of large net buy orders after market open to identify institutional activity[3][6] **Construction Process**: Derived from high-frequency trading data[30] **Evaluation**: Generally positive performance with strong returns in specific periods[3][6] 6. **Factor Name**: Post-Open Large Order Net Buy Intensity Factor **Construction Idea**: Measures the intensity of large net buy orders after market open to capture market trends[3][6] **Construction Process**: Derived from high-frequency trading data[35] **Evaluation**: Mixed results with moderate returns in some periods[3][6] 7. **Factor Name**: Improved Reversal Factor **Construction Idea**: Enhances traditional reversal factors by incorporating high-frequency data[3][6] **Construction Process**: Derived from intraday price reversals[40] **Evaluation**: Limited performance improvement over traditional reversal factors[3][6] 8. **Factor Name**: Tail-End Trading Proportion Factor **Construction Idea**: Measures the proportion of trading activity near market close to capture end-of-day effects[3][6] **Construction Process**: Derived from high-frequency trading data[45] **Evaluation**: Underperformance in most periods[3][6] 9. **Factor Name**: Average Single Transaction Outflow Proportion Factor **Construction Idea**: Tracks the proportion of outflows in single transactions to assess liquidity[3][6] **Construction Process**: Derived from high-frequency trading data[50] **Evaluation**: Limited effectiveness in predicting returns[3][6] 10. **Factor Name**: Large Order Push-Up Factor **Construction Idea**: Measures the impact of large orders on price increases to identify market movers[3][6] **Construction Process**: Derived from high-frequency trading data[55] **Evaluation**: Moderate performance with occasional strong returns[3][6] 11. **Factor Name**: Deep Learning High-Frequency Factor (Improved GRU(50,2)+NN(10)) **Construction Idea**: Combines GRU and neural networks to capture complex patterns in high-frequency data[3][6] **Construction Process**: Utilizes GRU(50,2) and NN(10) architectures for feature extraction and prediction[59] **Evaluation**: Strong performance in certain periods but underperformance in others[3][6] 12. **Factor Name**: Deep Learning High-Frequency Factor (Residual Attention LSTM(48,2)+NN(10)) **Construction Idea**: Incorporates residual attention mechanisms with LSTM and neural networks for enhanced prediction[3][6] **Construction Process**: Utilizes LSTM(48,2) and NN(10) architectures with residual attention layers[61] **Evaluation**: Consistently strong performance across multiple periods[3][6] 13. **Factor Name**: Deep Learning Factor (Multi-Granularity Model - 5-Day Label) **Construction Idea**: Uses multi-granularity modeling with 5-day labels for short-term predictions[3][6] **Construction Process**: Trained using bidirectional AGRU[64] **Evaluation**: Strong performance with high returns in most periods[3][6] 14. **Factor Name**: Deep Learning Factor (Multi-Granularity Model - 10-Day Label) **Construction Idea**: Uses multi-granularity modeling with 10-day labels for medium-term predictions[3][6] **Construction Process**: Trained using bidirectional AGRU[65] **Evaluation**: Consistently strong performance across multiple periods[3][6] AI-Enhanced Portfolio Construction 1. **Portfolio Name**: CSI 500 AI Enhanced Wide Constraint Portfolio **Construction Idea**: Maximizes expected returns under wide constraints using deep learning factors[69][70] **Construction Process**: - Weekly rebalancing - Constraints on individual stocks, industries, market cap, and other factors - Objective function: $$ max\sum\mu_{i}w_{i} $$ where \( w_i \) is the weight of stock \( i \) and \( \mu_i \) is its expected excess return[71] **Evaluation**: Strong cumulative excess returns since 2017[72] 2. **Portfolio Name**: CSI 500 AI Enhanced Strict Constraint Portfolio **Construction Idea**: Similar to the wide constraint portfolio but with stricter constraints[69][70] **Construction Process**: Same as above with stricter constraints on market cap, ROE, SUE, and volatility[71] **Evaluation**: Moderate cumulative excess returns since 2017[73] 3. **Portfolio Name**: CSI 1000 AI Enhanced Wide Constraint Portfolio **Construction Idea**: Maximizes expected returns under wide constraints using deep learning factors for smaller-cap stocks[69][70] **Construction Process**: Same as CSI 500 portfolios but applied to CSI 1000 index[71] **Evaluation**: Strong cumulative excess returns since 2017[76] 4. **Portfolio Name**: CSI 1000 AI Enhanced Strict Constraint Portfolio **Construction Idea**: Similar to the wide constraint portfolio but with stricter constraints for smaller-cap stocks[69][70] **Construction Process**: Same as above with stricter constraints on market cap, ROE, SUE, and volatility[71] **Evaluation**: Strong cumulative excess returns since 2017[79] Backtest Results for Factors 1. **Intraday Skewness Factor**: IC (2025): 0.057, Multi-Period Returns: 14.35% (2025)[3][6] 2. **Downside Volatility Proportion Factor**: IC (2025): 0.055, Multi-Period Returns: 11.77% (2025)[3][6] 3. **Post-Open Buy Intention Proportion Factor**: IC (2025): 0.033, Multi-Period Returns: 10.32% (2025)[3][6] 4. **Post-Open Buy Intention Intensity Factor**: IC (2025): 0.026, Multi-Period Returns: 11.19% (2025)[3][6] 5. **Post-Open Large Order Net Buy Proportion Factor**: IC (2025): 0.039, Multi-Period Returns: 12.32% (2025)[3][6] 6. **Post-Open Large Order Net Buy Intensity Factor**: IC (2025): 0.028, Multi-Period Returns: 6.78% (2025)[3][6] 7. **Improved Reversal Factor**: IC (2025): 0.003, Multi-Period Returns: 9.34% (2025)[3][6] 8. **Tail-End Trading Proportion Factor**: IC (2025): 0.022, Multi-Period Returns: 5.43% (2025)[3][6] 9. **Average Single Transaction Outflow Proportion Factor**: IC (2025): 0.012, Multi-Period Returns: 0.82% (2025)[3][6] 10. **Large Order Push-Up Factor