feat(factors): 集成 metadata 模块,支持按名称注册因子

- 新增 add_factor_by_name() 方法,从 metadata 查询 DSL 表达式并注册
- FactorEngine 支持可选的 metadata_path 参数初始化
- 将 regression.ipynb 和 learn_to_rank.ipynb 转换为 Python 脚本
- 新增 test_factor_engine_metadata.py 测试文件
This commit is contained in:
2026-03-11 22:54:52 +08:00
parent 038f5f1722
commit 2bb7718dd1
7 changed files with 2085 additions and 3101 deletions

View File

@@ -0,0 +1,792 @@
# %% md
# # Learn-to-Rank 排序学习训练流程
#
# 本 Notebook 实现基于 LightGBM LambdaRank 的排序学习训练,用于股票排序任务。
#
# ## 核心特点
#
# 1. **Label 转换**: 将 `future_return_5` 按每日进行 20 分位数划分qcut
# 2. **排序学习**: 使用 LambdaRank 目标函数,学习每日股票排序
# 3. **NDCG 评估**: 使用 NDCG@1/5/10/20 评估排序质量
# 4. **策略回测**: 基于排序分数构建 Top-k 选股策略
# %% md
# ## 1. 导入依赖
# %%
import os
from datetime import datetime
from typing import List, Tuple, Optional
import numpy as np
import polars as pl
import pandas as pd
import matplotlib.pyplot as plt
from sklearn.metrics import ndcg_score
from src.factors import FactorEngine
from src.training import (
DateSplitter,
STFilter,
StockPoolManager,
Trainer,
Winsorizer,
NullFiller,
StandardScaler,
)
from src.training.components.models import LightGBMLambdaRankModel
from src.training.config import TrainingConfig
# %% md
# ## 2. 辅助函数
# %%
def create_factors_with_metadata(
engine: FactorEngine, factor_definitions: dict, label_factor: dict
) -> List[str]:
"""使用 metadata 注册因子特征因子通过名称注册label 因子通过表达式注册)"""
print("=" * 80)
print("使用 metadata 注册因子")
print("=" * 80)
# 注册所有特征因子(通过 metadata 名称)
print("\n注册特征因子(从 metadata:")
for name in factor_definitions.keys():
engine.add_factor_by_name(name)
print(f" - {name}")
# 注册 label 因子(通过表达式,因为 label 不在 metadata 中)
print("\n注册 Label 因子(表达式):")
for name, expr in label_factor.items():
engine.add_factor(name, expr)
print(f" - {name}: {expr}")
# 从字典自动获取特征列
feature_cols = list(factor_definitions.keys())
print(f"\n特征因子数: {len(feature_cols)}")
print(f"Label: {list(label_factor.keys())[0]}")
print(f"已注册因子总数: {len(engine.list_registered())}")
return feature_cols
def prepare_data(
engine: FactorEngine,
feature_cols: List[str],
start_date: str,
end_date: str,
) -> pl.DataFrame:
"""准备数据"""
print("\n" + "=" * 80)
print("准备数据")
print("=" * 80)
# 计算因子(全市场数据)
print(f"\n计算因子: {start_date} - {end_date}")
factor_names = feature_cols + [LABEL_NAME] # 包含 label
data = engine.compute(
factor_names=factor_names,
start_date=start_date,
end_date=end_date,
)
print(f"数据形状: {data.shape}")
print(f"数据列: {data.columns}")
print(f"\n前5行预览:")
print(data.head())
return data
def prepare_ranking_data(
df: pl.DataFrame,
label_col: str = "future_return_5",
date_col: str = "trade_date",
n_quantiles: int = 20,
) -> Tuple[pl.DataFrame, str]:
"""准备排序学习数据
将连续 label 转换为分位数标签,用于排序学习任务。
Args:
df: 原始数据
label_col: 原始标签列名
date_col: 日期列名
n_quantiles: 分位数数量
Returns:
(处理后的 DataFrame, 新的标签列名)
"""
print("\n" + "=" * 80)
print(f"准备排序学习数据(将 {label_col} 转换为 {n_quantiles} 分位数标签)")
print("=" * 80)
# 新的标签列名
rank_col = f"{label_col}_rank"
# 按日期分组进行分位数划分
# 使用 rank 生成 0, 1, 2, ..., n_quantiles-1 的标签
# 方法: 计算每天内的排名,然后映射到 n_quantiles 个分位数组
df_ranked = (
df.with_columns(
# 计算每天内的排名 (1-based)
pl.col(label_col).rank(method="min").over(date_col).alias("_rank")
)
.with_columns(
# 将排名转换为分位数标签 (0 to n_quantiles-1)
((pl.col("_rank") - 1) / pl.len().over(date_col) * n_quantiles)
.floor()
.cast(pl.Int64)
.clip(0, n_quantiles - 1)
.alias(rank_col)
)
.drop("_rank")
)
# 检查转换结果
print(f"\n原始 {label_col} 统计:")
print(df_ranked[label_col].describe())
print(f"\n转换后 {rank_col} 统计:")
print(df_ranked[rank_col].describe())
# 检查每日样本分布
print(f"\n每日样本数统计:")
daily_counts = df_ranked.group_by(date_col).agg(pl.count().alias("count"))
print(daily_counts["count"].describe())
# 检查分位数分布(应该是均匀的)
print(f"\n分位数标签分布:")
rank_dist = df_ranked[rank_col].value_counts().sort(rank_col)
print(rank_dist)
return df_ranked, rank_col
def compute_group_array(df: pl.DataFrame, date_col: str = "trade_date") -> np.ndarray:
"""计算 group 数组用于 LambdaRank
每个日期作为一个 querygroup 数组表示每个 query 的样本数。
Args:
df: 数据框
date_col: 日期列名
Returns:
group 数组
"""
group_counts = df.group_by(date_col, maintain_order=True).agg(
pl.count().alias("count")
)
return group_counts["count"].to_numpy()
def evaluate_ndcg_at_k(
y_true: np.ndarray,
y_pred: np.ndarray,
group: np.ndarray,
k_list: List[int] = [1, 5, 10, 20],
) -> dict:
"""计算 NDCG@k 指标
Args:
y_true: 真实标签
y_pred: 预测分数
group: 分组数组
k_list: 要计算的 k 值列表
Returns:
NDCG 指标字典
"""
results = {}
# 按 group 拆分数据
start_idx = 0
y_true_groups = []
y_pred_groups = []
for group_size in group:
end_idx = start_idx + group_size
y_true_groups.append(y_true[start_idx:end_idx])
y_pred_groups.append(y_pred[start_idx:end_idx])
start_idx = end_idx
# 计算每个 k 值的平均 NDCG
for k in k_list:
ndcg_scores = []
for yt, yp in zip(y_true_groups, y_pred_groups):
if len(yt) > 1:
try:
score = ndcg_score([yt], [yp], k=k)
ndcg_scores.append(score)
except ValueError:
# 标签都相同,无法计算
pass
results[f"ndcg@{k}"] = np.mean(ndcg_scores) if ndcg_scores else 0.0
return results
# %% md
# ## 3. 配置参数
#
# ### 3.1 因子定义
# %%
# 特征因子定义字典(复用 regression.ipynb 的因子定义)
LABEL_NAME = "future_return_5_rank"
FACTOR_DEFINITIONS = {
# ================= 1. 价格、趋势与路径依赖 (Trend, Momentum & Path Dependency) =================
"ma_5": "ts_mean(close, 5)",
"ma_20": "ts_mean(close, 20)",
"ma_ratio_5_20": "ts_mean(close, 5) / (ts_mean(close, 20) + 1e-8) - 1",
"bias_10": "close / (ts_mean(close, 10) + 1e-8) - 1",
"high_low_ratio": "(close - ts_min(low, 20)) / (ts_max(high, 20) - ts_min(low, 20) + 1e-8)",
"bbi_ratio": "(ts_mean(close, 3) + ts_mean(close, 6) + ts_mean(close, 12) + ts_mean(close, 24)) / (4 * close + 1e-8)",
"return_5": "(close / (ts_delay(close, 5) + 1e-8)) - 1",
"return_20": "(close / (ts_delay(close, 20) + 1e-8)) - 1",
"kaufman_ER_20": "abs(close - ts_delay(close, 20)) / (ts_sum(abs(close - ts_delay(close, 1)), 20) + 1e-8)",
"mom_acceleration_10_20": "(close / (ts_delay(close, 10) + 1e-8) - 1) - (ts_delay(close, 10) / (ts_delay(close, 20) + 1e-8) - 1)",
"drawdown_from_high_60": "close / (ts_max(high, 60) + 1e-8) - 1",
"up_days_ratio_20": "ts_sum(close > ts_delay(close, 1), 20) / 20",
# ================= 2. 波动率、风险调整与高阶矩 =================
"volatility_5": "ts_std(close, 5)",
"volatility_20": "ts_std(close, 20)",
"volatility_ratio": "ts_std(close, 5) / (ts_std(close, 20) + 1e-8)",
"std_return_20": "ts_std((close / (ts_delay(close, 1) + 1e-8)) - 1, 20)",
"sharpe_ratio_20": "ts_mean(close / (ts_delay(close, 1) + 1e-8) - 1, 20) / (ts_std(close / (ts_delay(close, 1) + 1e-8) - 1, 20) + 1e-8)",
"min_ret_20": "ts_min(close / (ts_delay(close, 1) + 1e-8) - 1, 20)",
"volatility_squeeze_5_60": "ts_std(close, 5) / (ts_std(close, 60) + 1e-8)",
# ================= 3. 日内微观结构与异象 =================
"overnight_intraday_diff": "(open / (ts_delay(close, 1) + 1e-8) - 1) - (close / (open + 1e-8) - 1)",
"upper_shadow_ratio": "(high - ((open + close + abs(open - close)) / 2)) / (high - low + 1e-8)",
"capital_retention_20": "ts_sum(abs(close - open), 20) / (ts_sum(high - low, 20) + 1e-8)",
"max_ret_20": "ts_max(close / (ts_delay(close, 1) + 1e-8) - 1, 20)",
# ================= 4. 量能、流动性与量价背离 =================
"volume_ratio_5_20": "ts_mean(vol, 5) / (ts_mean(vol, 20) + 1e-8)",
"turnover_rate_mean_5": "ts_mean(turnover_rate, 5)",
"turnover_deviation": "(turnover_rate - ts_mean(turnover_rate, 10)) / (ts_std(turnover_rate, 10) + 1e-8)",
"amihud_illiq_20": "ts_mean(abs(close / (ts_delay(close, 1) + 1e-8) - 1) / (amount + 1e-8), 20)",
"turnover_cv_20": "ts_std(turnover_rate, 20) / (ts_mean(turnover_rate, 20) + 1e-8)",
"pv_corr_20": "ts_corr(close / (ts_delay(close, 1) + 1e-8) - 1, vol, 20)",
"close_vwap_deviation": "close / (amount / (vol * 100 + 1e-8) + 1e-8) - 1",
# ================= 5. 基本面财务特征 =================
"roe": "n_income / (total_hldr_eqy_exc_min_int + 1e-8)",
"roa": "n_income / (total_assets + 1e-8)",
"profit_margin": "n_income / (revenue + 1e-8)",
"debt_to_equity": "total_liab / (total_hldr_eqy_exc_min_int + 1e-8)",
"current_ratio": "total_cur_assets / (total_cur_liab + 1e-8)",
"net_profit_yoy": "(n_income / (ts_delay(n_income, 252) + 1e-8)) - 1",
"revenue_yoy": "(revenue / (ts_delay(revenue, 252) + 1e-8)) - 1",
"healthy_expansion_velocity": "(total_assets / (ts_delay(total_assets, 252) + 1e-8) - 1) - (total_liab / (ts_delay(total_liab, 252) + 1e-8) - 1)",
# ================= 6. 基本面估值与截面动量共振 =================
"EP": "n_income / (total_mv * 10000 + 1e-8)",
"BP": "total_hldr_eqy_exc_min_int / (total_mv * 10000 + 1e-8)",
"CP": "n_cashflow_act / (total_mv * 10000 + 1e-8)",
"market_cap_rank": "cs_rank(total_mv)",
"turnover_rank": "cs_rank(turnover_rate)",
"return_5_rank": "cs_rank((close / (ts_delay(close, 5) + 1e-8)) - 1)",
"EP_rank": "cs_rank(n_income / (total_mv + 1e-8))",
"pe_expansion_trend": "(total_mv / (n_income + 1e-8)) / (ts_delay(total_mv, 60) / (ts_delay(n_income, 60) + 1e-8) + 1e-8) - 1",
"value_price_divergence": "cs_rank((n_income - ts_delay(n_income, 252)) / (abs(ts_delay(n_income, 252)) + 1e-8)) - cs_rank(close / (ts_delay(close, 20) + 1e-8))",
"active_market_cap": "total_mv * ts_mean(turnover_rate, 20)",
"ebit_rank": "cs_rank(ebit)",
}
# Label 因子定义(不参与训练,用于计算目标)
LABEL_FACTOR = {
LABEL_NAME: "(ts_delay(close, -5) / ts_delay(open, -1)) - 1",
}
# %% md
# ### 3.2 训练参数配置
# %%
# 日期范围配置(正确的 train/val/test 三分法)
TRAIN_START = "20200101"
TRAIN_END = "20231231"
VAL_START = "20240101"
VAL_END = "20241231"
TEST_START = "20250101"
TEST_END = "20251231"
# LambdaRank 模型参数配置
MODEL_PARAMS = {
"objective": "lambdarank",
"metric": "ndcg",
"ndcg_at": [1, 5, 10, 20], # 评估 NDCG@k
"learning_rate": 0.05,
"num_leaves": 31,
"max_depth": 6,
"min_data_in_leaf": 20,
"n_estimators": 1000,
"early_stopping_rounds": 50,
"subsample": 0.8,
"colsample_bytree": 0.8,
"reg_alpha": 0.1,
"reg_lambda": 1.0,
"verbose": -1,
"random_state": 42,
}
# 分位数配置
N_QUANTILES = 20 # 将 label 分为 20 组
# 特征列(用于数据处理器)
FEATURE_COLS = list(FACTOR_DEFINITIONS.keys())
# 数据处理器配置
PROCESSORS = [
NullFiller(feature_cols=FEATURE_COLS, strategy="mean"),
Winsorizer(feature_cols=FEATURE_COLS, lower=0.01, upper=0.99),
StandardScaler(feature_cols=FEATURE_COLS),
]
# 股票池筛选函数
def stock_pool_filter(df: pl.DataFrame) -> pl.Series:
"""股票池筛选函数(单日数据)
筛选条件:
1. 排除创业板(代码以 300 开头)
2. 排除科创板(代码以 688 开头)
3. 排除北交所(代码以 8、9 或 4 开头)
4. 选取当日市值最小的500只股票
"""
code_filter = (
~df["ts_code"].str.starts_with("30")
& ~df["ts_code"].str.starts_with("68")
& ~df["ts_code"].str.starts_with("8")
& ~df["ts_code"].str.starts_with("9")
& ~df["ts_code"].str.starts_with("4")
)
valid_df = df.filter(code_filter)
n = min(1000, len(valid_df))
small_cap_codes = valid_df.sort("total_mv").head(n)["ts_code"]
return df["ts_code"].is_in(small_cap_codes)
STOCK_FILTER_REQUIRED_COLUMNS = ["total_mv"]
# 输出配置
OUTPUT_DIR = "output"
SAVE_PREDICTIONS = True
PERSIST_MODEL = False
# Top N 配置:每日推荐股票数量
TOP_N = 5 # 可调整为 10, 20 等
# %% md
# ## 4. 训练流程
# %%
print("\n" + "=" * 80)
print("LightGBM LambdaRank 排序学习训练")
print("=" * 80)
# 1. 创建 FactorEngine启用 metadata 功能)
print("\n[1] 创建 FactorEngine")
engine = FactorEngine(metadata_path="data/factors.jsonl")
# 2. 使用 metadata 定义因子
print("\n[2] 定义因子(从 metadata 注册)")
feature_cols = create_factors_with_metadata(engine, FACTOR_DEFINITIONS, LABEL_FACTOR)
# 3. 准备数据
print("\n[3] 准备数据")
data = prepare_data(
engine=engine,
feature_cols=feature_cols,
start_date=TRAIN_START,
end_date=TEST_END,
)
# 4. 转换为排序学习格式(分位数标签)
print("\n[4] 转换为排序学习格式")
data, target_col = prepare_ranking_data(
df=data,
label_col=LABEL_NAME,
n_quantiles=N_QUANTILES,
)
# 5. 打印配置信息
print(f"\n[配置] 训练期: {TRAIN_START} - {TRAIN_END}")
print(f"[配置] 验证期: {VAL_START} - {VAL_END}")
print(f"[配置] 测试期: {TEST_START} - {TEST_END}")
print(f"[配置] 特征数: {len(feature_cols)}")
print(f"[配置] 目标变量: {target_col}{N_QUANTILES}分位数)")
# 6. 创建排序学习模型
model = LightGBMLambdaRankModel(params=MODEL_PARAMS)
# 7. 创建数据处理器
processors = PROCESSORS
# 8. 创建数据划分器
splitter = DateSplitter(
train_start=TRAIN_START,
train_end=TRAIN_END,
val_start=VAL_START,
val_end=VAL_END,
test_start=TEST_START,
test_end=TEST_END,
)
# 9. 创建股票池管理器
pool_manager = StockPoolManager(
filter_func=stock_pool_filter,
required_columns=STOCK_FILTER_REQUIRED_COLUMNS,
data_router=engine.router,
)
# 10. 创建 ST 过滤器
st_filter = STFilter(data_router=engine.router)
# 11. 创建训练器
trainer = Trainer(
model=model,
pool_manager=pool_manager,
processors=processors,
filters=[st_filter],
splitter=splitter,
target_col=target_col,
feature_cols=feature_cols,
persist_model=PERSIST_MODEL,
)
# %% md
# ### 4.1 股票池筛选
# %%
print("\n" + "=" * 80)
print("股票池筛选")
print("=" * 80)
# 先执行 ST 过滤(在股票池筛选之前,与 Trainer.train() 保持一致)
if st_filter:
print("\n[过滤] 应用 ST 过滤器...")
data = st_filter.filter(data)
print(f" ST 过滤后数据规模: {data.shape}")
if pool_manager:
print("\n执行每日独立筛选股票池...")
filtered_data = pool_manager.filter_and_select_daily(data)
print(f" 筛选前数据规模: {data.shape}")
print(f" 筛选后数据规模: {filtered_data.shape}")
print(f" 筛选前股票数: {data['ts_code'].n_unique()}")
print(f" 筛选后股票数: {filtered_data['ts_code'].n_unique()}")
print(f" 删除记录数: {len(data) - len(filtered_data)}")
else:
filtered_data = data
print(" 未配置股票池管理器,跳过筛选")
# %% md
# ### 4.2 数据划分
# %%
print("\n" + "=" * 80)
print("数据划分")
print("=" * 80)
if splitter:
train_data, val_data, test_data = splitter.split(filtered_data)
print(f"\n训练集数据规模: {train_data.shape}")
print(f"验证集数据规模: {val_data.shape}")
print(f"测试集数据规模: {test_data.shape}")
# 计算各集的 group 数组
train_group = compute_group_array(train_data)
val_group = compute_group_array(val_data)
test_group = compute_group_array(test_data)
print(f"\n训练集 group 数量: {len(train_group)}")
print(f"验证集 group 数量: {len(val_group)}")
print(f"测试集 group 数量: {len(test_group)}")
print(f"训练集日均样本数: {np.mean(train_group):.1f}")
print(f"验证集日均样本数: {np.mean(val_group):.1f}")
print(f"测试集日均样本数: {np.mean(test_group):.1f}")
else:
raise ValueError("必须配置数据划分器")
# %% md
# ### 4.3 数据预处理
# %%
print("\n" + "=" * 80)
print("数据预处理")
print("=" * 80)
fitted_processors = []
if processors:
print("\n训练集处理...")
for i, processor in enumerate(processors, 1):
print(f" [{i}/{len(processors)}] {processor.__class__.__name__}")
train_data = processor.fit_transform(train_data)
fitted_processors.append(processor)
print("\n验证集处理...")
for processor in fitted_processors:
val_data = processor.transform(val_data)
print("\n测试集处理...")
for processor in fitted_processors:
test_data = processor.transform(test_data)
print(f"\n处理后训练集形状: {train_data.shape}")
print(f"处理后验证集形状: {val_data.shape}")
print(f"处理后测试集形状: {test_data.shape}")
# %% md
# ### 4.4 训练 LambdaRank 模型
# %%
print("\n" + "=" * 80)
print("训练 LambdaRank 模型")
print("=" * 80)
# 准备数据
X_train = train_data.select(feature_cols)
y_train = train_data.select(target_col).to_series()
X_val = val_data.select(feature_cols)
y_val = val_data.select(target_col).to_series()
print(f"\n训练样本数: {len(X_train)}")
print(f"验证样本数: {len(X_val)}")
print(f"特征数: {len(feature_cols)}")
print(f"目标变量: {target_col}")
print("\n目标变量统计(训练集):")
print(y_train.describe())
print("\n开始训练...")
model.fit(
X=X_train,
y=y_train,
group=train_group,
eval_set=(X_val, y_val, val_group),
)
print("训练完成!")
# %% md
# ### 4.5 训练指标曲线
# %%
print("\n" + "=" * 80)
print("训练指标曲线")
print("=" * 80)
# 重新训练以收集指标(因为之前的训练没有保存评估结果)
print("\n重新训练模型以收集训练指标...")
import lightgbm as lgb
# 准备数据(使用 val 做验证test 不参与训练过程)
X_train_np = X_train.to_numpy()
y_train_np = y_train.to_numpy()
X_val_np = val_data.select(feature_cols).to_numpy()
y_val_np = val_data.select(target_col).to_series().to_numpy()
# 创建数据集
train_dataset = lgb.Dataset(X_train_np, label=y_train_np, group=train_group)
val_dataset = lgb.Dataset(
X_val_np, label=y_val_np, group=val_group, reference=train_dataset
)
# 用于存储评估结果
evals_result = {}
# 使用与原模型相同的参数重新训练
# 正确的三分法train用于训练val用于验证test不参与训练过程
booster_with_eval = lgb.train(
MODEL_PARAMS,
train_dataset,
num_boost_round=MODEL_PARAMS.get("n_estimators", 1000),
valid_sets=[train_dataset, val_dataset],
valid_names=["train", "val"],
callbacks=[
lgb.record_evaluation(evals_result),
lgb.early_stopping(stopping_rounds=50, verbose=True),
],
)
print("训练完成,指标已收集")
# 获取评估的 NDCG 指标
ndcg_metrics = [k for k in evals_result["train"].keys() if "ndcg" in k]
print(f"\n评估的 NDCG 指标: {ndcg_metrics}")
# 显示早停信息
actual_rounds = len(list(evals_result["train"].values())[0])
expected_rounds = MODEL_PARAMS.get("n_estimators", 1000)
print(f"\n[早停信息]")
print(f" 配置的最大轮数: {expected_rounds}")
print(f" 实际训练轮数: {actual_rounds}")
if actual_rounds < expected_rounds:
print(f" 早停状态: 已触发连续50轮验证指标未改善")
else:
print(f" 早停状态: 未触发(达到最大轮数)")
# 显示各 NDCG 指标的最终值
print(f"\n最终 NDCG 指标:")
for metric in ndcg_metrics:
train_ndcg = evals_result["train"][metric][-1]
val_ndcg = evals_result["val"][metric][-1]
print(f" {metric}: 训练集={train_ndcg:.4f}, 验证集={val_ndcg:.4f}")
# %%
# 绘制 NDCG 训练指标曲线
import matplotlib.pyplot as plt
fig, axes = plt.subplots(2, 2, figsize=(14, 10))
axes = axes.flatten()
for idx, metric in enumerate(ndcg_metrics[:4]): # 最多显示4个NDCG指标
ax = axes[idx]
train_metric = evals_result["train"][metric]
val_metric = evals_result["val"][metric]
iterations = range(1, len(train_metric) + 1)
ax.plot(
iterations, train_metric, label=f"Train {metric}", linewidth=2, color="blue"
)
ax.plot(iterations, val_metric, label=f"Val {metric}", linewidth=2, color="red")
ax.set_xlabel("Iteration", fontsize=10)
ax.set_ylabel(metric.upper(), fontsize=10)
ax.set_title(
f"Training and Validation {metric.upper()}", fontsize=12, fontweight="bold"
)
ax.legend(fontsize=9)
ax.grid(True, alpha=0.3)
# 标记最佳验证指标点
best_iter = val_metric.index(max(val_metric))
best_metric = max(val_metric)
ax.axvline(x=best_iter + 1, color="green", linestyle="--", alpha=0.7)
ax.scatter([best_iter + 1], [best_metric], color="green", s=80, zorder=5)
ax.annotate(
f"Best: {best_metric:.4f}",
xy=(best_iter + 1, best_metric),
xytext=(best_iter + 1 + len(iterations) * 0.05, best_metric),
fontsize=8,
arrowprops=dict(arrowstyle="->", color="green", alpha=0.7),
)
plt.tight_layout()
plt.show()
print(f"\n[指标分析]")
print(f" 各NDCG指标在验证集上的最佳值:")
for metric in ndcg_metrics:
val_metric_list = evals_result["val"][metric]
best_iter = val_metric_list.index(max(val_metric_list))
best_val = max(val_metric_list)
print(f" {metric}: {best_val:.4f} (迭代 {best_iter + 1})")
print(f"\n[重要提醒] 验证集仅用于早停/调参,测试集完全独立于训练过程!")
# %% md
# ### 4.6 模型评估
# %%
print("\n" + "=" * 80)
print("模型评估")
print("=" * 80)
# 准备测试集
X_test = test_data.select(feature_cols)
y_test = test_data.select(target_col).to_series()
# 预测
print("\n生成预测...")
predictions = model.predict(X_test)
# 添加预测列
test_data = test_data.with_columns([pl.Series("prediction", predictions)])
# 计算 NDCG 指标
print("\n计算 NDCG 指标...")
ndcg_results = evaluate_ndcg_at_k(
y_true=y_test.to_numpy(),
y_pred=predictions,
group=test_group,
k_list=[1, 5, 10, 20],
)
print("\nNDCG 评估结果:")
print("-" * 40)
for metric, value in ndcg_results.items():
print(f" {metric}: {value:.4f}")
# 特征重要性
print("\n特征重要性Top 20:")
print("-" * 40)
importance = model.feature_importance()
if importance is not None:
top_features = importance.sort_values(ascending=False).head(20)
for i, (feature, score) in enumerate(top_features.items(), 1):
print(f" {i:2d}. {feature:30s} {score:10.2f}")
# %%
# 确保输出目录存在
os.makedirs(OUTPUT_DIR, exist_ok=True)
# 生成时间戳
start_dt = datetime.strptime(TEST_START, "%Y%m%d")
end_dt = datetime.strptime(TEST_END, "%Y%m%d")
date_str = f"{start_dt.strftime('%Y%m%d')}_{end_dt.strftime('%Y%m%d')}"
# 保存每日 Top N
print(f"\n[1/1] 保存每日 Top {TOP_N} 股票...")
topn_output_path = os.path.join(OUTPUT_DIR, "rank_output.csv")
# 按日期分组,取每日 top N
topn_by_date = []
unique_dates = test_data["trade_date"].unique().sort()
for date in unique_dates:
day_data = test_data.filter(test_data["trade_date"] == date)
# 按 prediction 降序排序,取前 N
topn = day_data.sort("prediction", descending=True).head(TOP_N)
topn_by_date.append(topn)
# 合并所有日期的 top N
topn_results = pl.concat(topn_by_date)
# 格式化日期并调整列顺序:日期、分数、股票
topn_to_save = topn_results.select(
[
pl.col("trade_date").str.slice(0, 4)
+ "-"
+ pl.col("trade_date").str.slice(4, 2)
+ "-"
+ pl.col("trade_date").str.slice(6, 2).alias("date"),
pl.col("prediction").alias("score"),
pl.col("ts_code"),
]
)
topn_to_save.write_csv(topn_output_path, include_header=True)
print(f" 保存路径: {topn_output_path}")
print(
f" 保存行数: {len(topn_to_save)}{len(unique_dates)}个交易日 x 每日top{TOP_N}"
)
print(f"\n 预览前15行:")
print(topn_to_save.head(15))
print("\n训练流程完成!")
# %% md
# ## 5. 总结
#
# 本 Notebook 实现了完整的 Learn-to-Rank 训练流程:
#
# ### 核心步骤
#
# 1. **数据准备**: 计算 49 个特征因子,将 `future_return_5` 转换为 20 分位数标签
# 2. **模型训练**: 使用 LightGBM LambdaRank 学习每日股票排序
# 3. **模型评估**: 使用 NDCG@1/5/10/20 评估排序质量
# 4. **策略分析**: 基于排序分数构建 Top-k 选股策略
#
# ### 关键参数
#
# - **Objective**: lambdarank
# - **Metric**: ndcg
# - **Learning Rate**: 0.05
# - **Num Leaves**: 31
# - **N Quantiles**: 20
#
# ### 输出结果
#
# - rank_output.csv: 每日Top-N推荐股票格式date, score, ts_code
# - 特征重要性排名
# - Top-k 策略统计和图表
# - NDCG训练指标曲线
#
# ### 后续优化方向
#
# 1. **特征工程**: 尝试更多因子组合
# 2. **超参数调优**: 使用网格搜索优化 LambdaRank 参数
# 3. **模型集成**: 结合多个排序模型的预测
# 4. **更复杂的分组**: 考虑按行业分组排序