import numpy as np
import matplotlib.pyplot as plt
from sklearn.utils.validation import check_consistent_length
from ..metrics import uplift_curve, auuc, qini_curve, auqc, response_rate_by_percentile, treatment_balance_curve
[docs]def plot_uplift_preds(trmnt_preds, ctrl_preds, log=False, bins=100):
"""Plot histograms of treatment, control and uplift predictions.
Args:
trmnt_preds (1d array-like): Predictions for all observations if they are treatment.
ctrl_preds (1d array-like): Predictions for all observations if they are control.
log (bool, default False): Logarithm of source samples.
bins (integer or sequence, default 100): Number of histogram bins to be used.
If an integer is given, bins + 1 bin edges are calculated and returned.
If bins is a sequence, gives bin edges, including left edge of first bin and right edge of last bin.
In this case, bins is returned unmodified.
Returns:
Object that stores computed values.
"""
# TODO: Add k as parameter: vertical line on plots
check_consistent_length(trmnt_preds, ctrl_preds)
if not isinstance(bins, int) or bins <= 0:
raise ValueError(f'Bins should be positive integer. Invalid value for bins: {bins}')
if log:
trmnt_preds = np.log(trmnt_preds + 1)
ctrl_preds = np.log(ctrl_preds + 1)
fig, axes = plt.subplots(ncols=3, nrows=1, figsize=(20, 7))
axes[0].hist(
trmnt_preds, bins=bins, alpha=0.3, color='b', label='Treated', histtype='stepfilled')
axes[0].set_ylabel('Probability hist')
axes[0].legend()
axes[0].set_title('Treatment predictions')
axes[1].hist(
ctrl_preds, bins=bins, alpha=0.5, color='y', label='Not treated', histtype='stepfilled')
axes[1].legend()
axes[1].set_title('Control predictions')
axes[2].hist(
trmnt_preds - ctrl_preds, bins=bins, alpha=0.5, color='green', label='Uplift', histtype='stepfilled')
axes[2].legend()
axes[2].set_title('Uplift predictions')
return axes
[docs]def plot_uplift_qini_curves(y_true, uplift, treatment, random=True, perfect=False):
"""Plot Uplift and Qini curves.
Args:
y_true (1d array-like): Ground truth (correct) labels.
uplift (1d array-like): Predicted uplift, as returned by a model.
treatment (1d array-like): Treatment labels.
random (bool, default True): Draw a random curve.
perfect (bool, default False): Draw a perfect curve.
Returns:
Object that stores computed values.
"""
check_consistent_length(y_true, uplift, treatment)
y_true, uplift, treatment = np.array(y_true), np.array(uplift), np.array(treatment)
x_up, y_up = uplift_curve(y_true, uplift, treatment)
x_qi, y_qi = qini_curve(y_true, uplift, treatment)
fig, axes = plt.subplots(ncols=2, nrows=1, figsize=(14, 7))
axes[0].plot(x_up, y_up, label='Model', color='b')
axes[1].plot(x_qi, y_qi, label='Model', color='b')
if random:
up_ratio_random = (y_true[treatment == 1].sum() / len(y_true[treatment == 1]) -
y_true[treatment == 0].sum() / len(y_true[treatment == 0]))
y_up_random = x_up * up_ratio_random
qi_ratio_random = (y_true[treatment == 1].sum() - len(y_true[treatment == 1]) *
y_true[treatment == 0].sum() / len(y_true[treatment == 0])) / len(y_true)
y_qi_random = x_qi * qi_ratio_random
axes[0].plot(x_up, y_up_random, label='Random', color='black')
axes[0].fill_between(x_up, y_up, y_up_random, alpha=0.2, color='b')
axes[1].plot(x_qi, y_qi_random, label='Random', color='black')
axes[1].fill_between(x_qi, y_qi, y_qi_random, alpha=0.2, color='b')
if perfect:
x_up_perfect, y_up_perfect = uplift_curve(
y_true, y_true * treatment - y_true * (1 - treatment), treatment
)
x_qi_perfect, y_qi_perfect = qini_curve(
y_true, y_true * treatment - y_true * (1 - treatment), treatment
)
axes[0].plot(x_up_perfect, y_up_perfect, label='Perfect', color='red')
axes[1].plot(x_qi_perfect, y_qi_perfect, label='Perfect', color='red')
axes[0].legend(loc='upper left')
axes[0].set_title(f'Uplift curve: AUUC={auuc(y_true, uplift, treatment):.2f}')
axes[0].set_xlabel('Number targeted')
axes[0].set_ylabel('Relative gain: treatment - control')
axes[1].legend(loc='upper left')
axes[1].set_title(f'Qini curve: AUQC={auqc(y_true, uplift, treatment):.2f}')
axes[1].set_xlabel('Number targeted')
axes[1].set_ylabel('Number of incremental outcome')
return axes
[docs]def plot_uplift_by_percentile(y_true, uplift, treatment, strategy, kind='line', bins=10):
"""Plot uplift score, treatment response rate and control response rate at each percentile.
Treatment response rate ia a target mean in the treatment group.
Control response rate is a target mean in the control group.
Uplift score is a difference between treatment response rate and control response rate.
Args:
y_true (1d array-like): Correct (true) target values.
uplift (1d array-like): Predicted uplift, as returned by a model.
treatment (1d array-like): Treatment labels.
strategy (string, ['overall', 'by_group']): Determines the calculating strategy.
* ``'overall'``:
The first step is taking the first k observations of all test data ordered by uplift prediction
(overall both groups - control and treatment) and conversions in treatment and control groups
calculated only on them. Then the difference between these conversions is calculated.
* ``'by_group'``:
Separately calculates conversions in top k observations in each group (control and treatment)
sorted by uplift predictions. Then the difference between these conversions is calculated.
kind (string, ['line', 'bar']): The type of plot to draw. Default is 'line'.
* ``'line'``:
Generates a line plot.
* ``'bar'``:
Generates a traditional bar-style plot.
bins (int): Determines а number of bins (and а relative percentile) in the test data. Default is 10.
Returns:
Object that stores computed values.
"""
strategy_methods = ['overall', 'by_group']
kind_methods = ['line', 'bar']
n_samples = len(y_true)
check_consistent_length(y_true, uplift, treatment)
if strategy not in strategy_methods:
raise ValueError(f'Response rate supports only calculating methods in {strategy_methods},'
f' got {strategy}.')
if kind not in kind_methods:
raise ValueError(f'Function supports only types of plots in {kind_methods},'
f' got {kind}.')
if not isinstance(bins, int) or bins <= 0:
raise ValueError(f'Bins should be positive integer. Invalid value bins: {bins}')
if bins >= n_samples:
raise ValueError(f'Number of bins = {bins} should be smaller than the length of y_true {n_samples}')
rspns_rate_trmnt, var_trmnt = response_rate_by_percentile(y_true, uplift,
treatment, group='treatment',
strategy=strategy, bins=bins)
rspns_rate_ctrl, var_ctrl = response_rate_by_percentile(y_true, uplift,
treatment, group='control',
strategy=strategy, bins=bins)
uplift_score, uplift_variance = np.subtract(rspns_rate_trmnt, rspns_rate_ctrl), np.add(var_trmnt, var_ctrl)
percentiles = [p * 100 / bins for p in range(1, bins + 1)]
if kind == 'line':
_, axes = plt.subplots(ncols=1, nrows=1, figsize=(8, 6))
axes.errorbar(percentiles, uplift_score, yerr=np.sqrt(uplift_variance),
linewidth=2, color='red', label='uplift')
axes.errorbar(percentiles, rspns_rate_trmnt, yerr=np.sqrt(var_trmnt),
linewidth=2, color='forestgreen', label='treatment\nresponse rate')
axes.errorbar(percentiles, rspns_rate_ctrl, yerr=np.sqrt(var_ctrl),
linewidth=2, color='orange', label='control\nresponse rate')
axes.fill_between(percentiles, rspns_rate_ctrl, rspns_rate_trmnt, alpha=0.1, color='red')
if np.amin(uplift_score) < 0:
axes.axhline(y=0, color='black', linewidth=1)
axes.set_xticks(percentiles)
axes.legend(loc='upper right')
axes.set_title('Uplift by percentile')
axes.set_xlabel('Percentile')
axes.set_ylabel('Uplift = treatment response rate - control response rate')
else: # kind == 'bar'
delta = percentiles[0]
fig, axes = plt.subplots(ncols=1, nrows=2, figsize=(8, 6), sharex=True, sharey=True)
fig.text(0.04, 0.5, 'Uplift = treatment response rate - control response rate',
va='center', ha='center', rotation='vertical')
axes[0].bar(np.array(percentiles), uplift_score, delta / 1.5,
yerr=np.sqrt(uplift_variance), color='red', label='uplift')
axes[1].bar(np.array(percentiles) - delta / 6, rspns_rate_trmnt, delta / 3,
yerr=np.sqrt(var_trmnt), color='forestgreen', label='treatment\nresponse rate')
axes[1].bar(np.array(percentiles) + delta / 6, rspns_rate_ctrl, delta / 3,
yerr=np.sqrt(var_ctrl), color='orange', label='control\nresponse rate')
axes[0].legend(loc='upper right')
axes[0].tick_params(axis='x', bottom=False)
axes[0].axhline(y=0, color='black', linewidth=1)
axes[0].set_title('Uplift by percentile')
axes[1].set_xticks(percentiles)
axes[1].legend(loc='upper right')
axes[1].axhline(y=0, color='black', linewidth=1)
axes[1].set_xlabel('Percentile')
axes[1].set_title('Response rate by percentile')
return axes
[docs]def plot_treatment_balance_curve(uplift, treatment, random=True, winsize=0.1):
"""Plot Treatment Balance curve.
Args:
uplift (1d array-like): Predicted uplift, as returned by a model.
treatment (1d array-like): Treatment labels.
random (bool, default True): Draw a random curve.
winsize (float, default 0.1): Size of the sliding window to apply. Should be between 0 and 1, extremes excluded.
Returns:
Object that stores computed values.
"""
if (winsize <= 0) or (winsize >= 1):
raise ValueError('winsize should be between 0 and 1, extremes excluded')
x_tb, y_tb = treatment_balance_curve(uplift, treatment, winsize=int(len(uplift)*winsize))
_, axes = plt.subplots(ncols=1, nrows=1, figsize=(14, 7))
axes.plot(x_tb, y_tb, label='Model', color='b')
if random:
y_tb_random = np.average(treatment) * np.ones_like(x_tb)
axes.plot(x_tb, y_tb_random, label='Random', color='black')
axes.fill_between(x_tb, y_tb, y_tb_random, alpha=0.2, color='b')
axes.legend()
axes.set_title('Treatment balance curve')
axes.set_xlabel('Percentage targeted')
axes.set_ylabel('Balance: treatment / (treatment + control)')
return axes