Files
drift/utils/evaluate.py
T
Mark Aron Szulyovszky f85ee6bb9c fix(MetaLabeling): previously misinterpreted meta-labeling, now also multiplying base model's prediction with the meta model's prediction (#193)
* fix(MetaLabeling): previously misinterpreted meta-labeling, now also multiplying base model's prediction with the meta model's prediction

* fix(Evaluate): print results

* fix(Evaluate): make sure we have numerical stability in returns

* fix(Inference): only output and print stats in training mode

* fix(Evaluate): don't add miniscule amount to result
2022-02-01 13:09:00 +01:00

103 lines
4.5 KiB
Python

from typing import Literal, Callable
from sklearn.metrics import accuracy_score, f1_score, precision_score, recall_score
from quantstats.stats import skew, sortino
from utils.metrics import probabilistic_sharpe_ratio, sharpe_ratio
from utils.helpers import get_first_valid_return_index
import pandas as pd
import numpy as np
from data_loader.types import ForwardReturnSeries, ySeries
from training.types import Stats, WeightsSeries
def backtest(returns: pd.Series, signal: pd.Series, transaction_cost = 0.002) -> pd.Series:
delta_pos = signal.diff(1).abs().fillna(0.)
costs = transaction_cost * delta_pos
return (signal * returns) - costs
def __preprocess(forward_returns: ForwardReturnSeries, y_pred: pd.Series, y_true: pd.Series, no_of_classes: Literal['two', 'three-balanced', 'three-imbalanced'], discretize: bool) -> pd.DataFrame:
y_pred.name = 'y_pred'
forward_returns.name = 'forward_returns'
df = pd.concat([y_pred, forward_returns],axis=1).dropna()
discretize_func = get_discretize_function(no_of_classes)
# make sure that we evaluate binary/three-way predictions even if the model is a regression
df['sign_pred'] = df.y_pred.apply(discretize_func) if discretize else df.y_pred
df['sign_true'] = y_true
df['result'] = backtest(df.forward_returns, df.sign_pred)
return df
def evaluate_predictions(
forward_returns: ForwardReturnSeries,
y_pred: WeightsSeries,
y_true: ySeries,
no_of_classes: Literal['two', 'three-balanced', 'three-imbalanced'],
discretize: bool = False,
) -> Stats:
# ignore the predictions until we see a non-zero returns (and definitely skip the first sliding_window_size)
evaluate_from = max(get_first_valid_return_index(forward_returns), get_first_valid_return_index(y_pred))
forward_returns = pd.Series(forward_returns[evaluate_from:])
y_pred = pd.Series(y_pred[evaluate_from:])
df = __preprocess(forward_returns, y_pred, y_true, no_of_classes, discretize)
scorecard = dict()
def count_non_zero(series: pd.Series) -> int:
return len(series[series != 0])
no_of_samples = count_non_zero(df.y_pred)
scorecard['no_of_samples'] = no_of_samples
sharpe = sharpe_ratio(df.result)
scorecard['sharpe'] = sharpe
benchmark_sharpe = sharpe_ratio(df.forward_returns)
scorecard['benchmark_sharpe'] = benchmark_sharpe
scorecard['prob_sharpe'] = probabilistic_sharpe_ratio(sharpe, benchmark_sharpe, no_of_samples)
scorecard['sortino'] = sortino(df.result)
scorecard['skew'] = skew(df.result)
labels = [1, -1] if no_of_classes == 'two' else [1, -1, 0]
avg_type = 'weighted' if no_of_classes == 'two' else 'macro'
if discretize == True:
scorecard['accuracy'] = accuracy_score(df.sign_true, df.sign_pred) * 100
scorecard['recall'] = recall_score(df.sign_true, df.sign_pred, labels = labels, average=avg_type)
scorecard['precision'] = precision_score(df.sign_true, df.sign_pred, labels = labels, average=avg_type)
scorecard['f1_score'] = f1_score(df.sign_true, df.sign_pred, labels = labels, average=avg_type)
scorecard['edge'] = df.result.mean()
scorecard['noise'] = df.y_pred.diff().abs().mean()
scorecard['edge_to_noise'] = scorecard['edge'] / (scorecard['noise'] + 0.00001)
if discretize == True:
for index, row in df.sign_true.value_counts().iteritems():
scorecard['sign_true_ratio_' + str(index)] = row / len(df.sign_true)
for index, row in df.sign_pred.value_counts().iteritems():
scorecard['sign_pred_ratio_' + str(index)] = row / len(df.sign_pred)
scorecard = {k: round(float(v), 3) for k, v in scorecard.items()}
return scorecard
def __discretize_binary(x): return 1 if x > 0 else -1
def __discretize_threeway(x): return 0 if x == 0 else 1 if x > 0 else -1
def discretize_threeway_threshold(threshold: float) -> Callable:
def discretize(current_value):
lower_threshold = -threshold
upper_threshold = threshold
if np.isnan(current_value):
return np.nan
elif current_value <= lower_threshold:
return -1
elif current_value > lower_threshold and current_value < upper_threshold:
return 0
else:
return 1
return discretize
def get_discretize_function(no_of_classes: Literal['two', 'three-balanced', 'three-imbalanced']) -> Callable:
return __discretize_binary if no_of_classes == 'two' else __discretize_threeway