AIM-PIbd-32-Kurbanova-A-A/aimenv/Lib/site-packages/statsmodels/duration/tests/test_phreg.py

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2024-10-02 22:15:59 +04:00
import itertools
import os
import numpy as np
from statsmodels.duration.hazard_regression import PHReg
from numpy.testing import (assert_allclose,
assert_equal, assert_)
import pandas as pd
import pytest
# TODO: Include some corner cases: data sets with empty strata, strata
# with no events, entry times after censoring times, etc.
# All the R results
from .results import survival_r_results
from .results import survival_enet_r_results
"""
Tests of PHReg against R coxph.
Tests include entry times and stratification.
phreg_gentests.py generates the test data sets and puts them into the
results folder.
survival.R runs R on all the test data sets and constructs the
survival_r_results module.
"""
# Arguments passed to the PHReg fit method.
args = {"method": "bfgs", "disp": 0}
def get_results(n, p, ext, ties):
if ext is None:
coef_name = "coef_%d_%d_%s" % (n, p, ties)
se_name = "se_%d_%d_%s" % (n, p, ties)
time_name = "time_%d_%d_%s" % (n, p, ties)
hazard_name = "hazard_%d_%d_%s" % (n, p, ties)
else:
coef_name = "coef_%d_%d_%s_%s" % (n, p, ext, ties)
se_name = "se_%d_%d_%s_%s" % (n, p, ext, ties)
time_name = "time_%d_%d_%s_%s" % (n, p, ext, ties)
hazard_name = "hazard_%d_%d_%s_%s" % (n, p, ext, ties)
coef = getattr(survival_r_results, coef_name)
se = getattr(survival_r_results, se_name)
time = getattr(survival_r_results, time_name)
hazard = getattr(survival_r_results, hazard_name)
return coef, se, time, hazard
class TestPHReg:
# Load a data file from the results directory
@staticmethod
def load_file(fname):
cur_dir = os.path.dirname(os.path.abspath(__file__))
data = np.genfromtxt(os.path.join(cur_dir, 'results', fname),
delimiter=" ")
time = data[:,0]
status = data[:,1]
entry = data[:,2]
exog = data[:,3:]
return time, status, entry, exog
# Run a single test against R output
@staticmethod
def do1(fname, ties, entry_f, strata_f):
# Read the test data.
time, status, entry, exog = TestPHReg.load_file(fname)
n = len(time)
vs = fname.split("_")
n = int(vs[2])
p = int(vs[3].split(".")[0])
ties1 = ties[0:3]
# Needs to match the kronecker statement in survival.R
strata = np.kron(range(5), np.ones(n // 5))
# No stratification or entry times
mod = PHReg(time, exog, status, ties=ties)
phrb = mod.fit(**args)
coef_r, se_r, time_r, hazard_r = get_results(n, p, None, ties1)
assert_allclose(phrb.params, coef_r, rtol=1e-3)
assert_allclose(phrb.bse, se_r, rtol=1e-4)
time_h, cumhaz, surv = phrb.baseline_cumulative_hazard[0]
# Entry times but no stratification
phrb = PHReg(time, exog, status, entry=entry,
ties=ties).fit(**args)
coef, se, time_r, hazard_r = get_results(n, p, "et", ties1)
assert_allclose(phrb.params, coef, rtol=1e-3)
assert_allclose(phrb.bse, se, rtol=1e-3)
# Stratification but no entry times
phrb = PHReg(time, exog, status, strata=strata,
ties=ties).fit(**args)
coef, se, time_r, hazard_r = get_results(n, p, "st", ties1)
assert_allclose(phrb.params, coef, rtol=1e-4)
assert_allclose(phrb.bse, se, rtol=1e-4)
# Stratification and entry times
phrb = PHReg(time, exog, status, entry=entry,
strata=strata, ties=ties).fit(**args)
coef, se, time_r, hazard_r = get_results(n, p, "et_st", ties1)
assert_allclose(phrb.params, coef, rtol=1e-3)
assert_allclose(phrb.bse, se, rtol=1e-4)
#smoke test
time_h, cumhaz, surv = phrb.baseline_cumulative_hazard[0]
def test_missing(self):
np.random.seed(34234)
time = 50 * np.random.uniform(size=200)
status = np.random.randint(0, 2, 200).astype(np.float64)
exog = np.random.normal(size=(200,4))
time[0:5] = np.nan
status[5:10] = np.nan
exog[10:15,:] = np.nan
md = PHReg(time, exog, status, missing='drop')
assert_allclose(len(md.endog), 185)
assert_allclose(len(md.status), 185)
assert_allclose(md.exog.shape, np.r_[185,4])
def test_formula(self):
np.random.seed(34234)
time = 50 * np.random.uniform(size=200)
status = np.random.randint(0, 2, 200).astype(np.float64)
exog = np.random.normal(size=(200,4))
entry = np.zeros_like(time)
entry[0:10] = time[0:10] / 2
df = pd.DataFrame({"time": time, "status": status,
"exog1": exog[:, 0], "exog2": exog[:, 1],
"exog3": exog[:, 2], "exog4": exog[:, 3],
"entry": entry})
mod1 = PHReg(time, exog, status, entry=entry)
rslt1 = mod1.fit()
# works with "0 +" on RHS but issues warning
fml = "time ~ exog1 + exog2 + exog3 + exog4"
mod2 = PHReg.from_formula(fml, df, status=status,
entry=entry)
rslt2 = mod2.fit()
mod3 = PHReg.from_formula(fml, df, status="status",
entry="entry")
rslt3 = mod3.fit()
assert_allclose(rslt1.params, rslt2.params)
assert_allclose(rslt1.params, rslt3.params)
assert_allclose(rslt1.bse, rslt2.bse)
assert_allclose(rslt1.bse, rslt3.bse)
def test_formula_cat_interactions(self):
time = np.r_[1, 2, 3, 4, 5, 6, 7, 8, 9]
status = np.r_[1, 1, 0, 0, 1, 0, 1, 1, 1]
x1 = np.r_[1, 1, 1, 2, 2, 2, 3, 3, 3]
x2 = np.r_[1, 2, 3, 1, 2, 3, 1, 2, 3]
df = pd.DataFrame({"time": time, "status": status,
"x1": x1, "x2": x2})
model1 = PHReg.from_formula("time ~ C(x1) + C(x2) + C(x1)*C(x2)", status="status",
data=df)
assert_equal(model1.exog.shape, [9, 8])
def test_predict_formula(self):
n = 100
np.random.seed(34234)
time = 50 * np.random.uniform(size=n)
status = np.random.randint(0, 2, n).astype(np.float64)
exog = np.random.uniform(1, 2, size=(n, 2))
df = pd.DataFrame({"time": time, "status": status,
"exog1": exog[:, 0], "exog2": exog[:, 1]})
# Works with "0 +" on RHS but issues warning
fml = "time ~ exog1 + np.log(exog2) + exog1*exog2"
model1 = PHReg.from_formula(fml, df, status=status)
result1 = model1.fit()
from patsy import dmatrix
dfp = dmatrix(model1.data.design_info, df)
pr1 = result1.predict()
pr2 = result1.predict(exog=df)
pr3 = model1.predict(result1.params, exog=dfp) # No standard errors
pr4 = model1.predict(result1.params,
cov_params=result1.cov_params(),
exog=dfp)
prl = (pr1, pr2, pr3, pr4)
for i in range(4):
for j in range(i):
assert_allclose(prl[i].predicted_values,
prl[j].predicted_values)
prl = (pr1, pr2, pr4)
for i in range(3):
for j in range(i):
assert_allclose(prl[i].standard_errors, prl[j].standard_errors)
def test_formula_args(self):
np.random.seed(34234)
n = 200
time = 50 * np.random.uniform(size=n)
status = np.random.randint(0, 2, size=n).astype(np.float64)
exog = np.random.normal(size=(200, 2))
offset = np.random.uniform(size=n)
entry = np.random.uniform(0, 1, size=n) * time
df = pd.DataFrame({"time": time, "status": status, "x1": exog[:, 0],
"x2": exog[:, 1], "offset": offset, "entry": entry})
model1 = PHReg.from_formula("time ~ x1 + x2", status="status", offset="offset",
entry="entry", data=df)
result1 = model1.fit()
model2 = PHReg.from_formula("time ~ x1 + x2", status=df.status, offset=df.offset,
entry=df.entry, data=df)
result2 = model2.fit()
assert_allclose(result1.params, result2.params)
assert_allclose(result1.bse, result2.bse)
def test_offset(self):
np.random.seed(34234)
time = 50 * np.random.uniform(size=200)
status = np.random.randint(0, 2, 200).astype(np.float64)
exog = np.random.normal(size=(200,4))
for ties in "breslow", "efron":
mod1 = PHReg(time, exog, status)
rslt1 = mod1.fit()
offset = exog[:,0] * rslt1.params[0]
exog = exog[:, 1:]
mod2 = PHReg(time, exog, status, offset=offset, ties=ties)
rslt2 = mod2.fit()
assert_allclose(rslt2.params, rslt1.params[1:])
def test_post_estimation(self):
# All regression tests
np.random.seed(34234)
time = 50 * np.random.uniform(size=200)
status = np.random.randint(0, 2, 200).astype(np.float64)
exog = np.random.normal(size=(200,4))
mod = PHReg(time, exog, status)
rslt = mod.fit()
mart_resid = rslt.martingale_residuals
assert_allclose(np.abs(mart_resid).sum(), 120.72475743348433)
w_avg = rslt.weighted_covariate_averages
assert_allclose(np.abs(w_avg[0]).sum(0),
np.r_[7.31008415, 9.77608674,10.89515885, 13.1106801])
bc_haz = rslt.baseline_cumulative_hazard
v = [np.mean(np.abs(x)) for x in bc_haz[0]]
w = np.r_[23.482841556421608, 0.44149255358417017,
0.68660114081275281]
assert_allclose(v, w)
score_resid = rslt.score_residuals
v = np.r_[ 0.50924792, 0.4533952, 0.4876718, 0.5441128]
w = np.abs(score_resid).mean(0)
assert_allclose(v, w)
groups = np.random.randint(0, 3, 200)
mod = PHReg(time, exog, status)
rslt = mod.fit(groups=groups)
robust_cov = rslt.cov_params()
v = [0.00513432, 0.01278423, 0.00810427, 0.00293147]
w = np.abs(robust_cov).mean(0)
assert_allclose(v, w, rtol=1e-6)
s_resid = rslt.schoenfeld_residuals
ii = np.flatnonzero(np.isfinite(s_resid).all(1))
s_resid = s_resid[ii, :]
v = np.r_[0.85154336, 0.72993748, 0.73758071, 0.78599333]
assert_allclose(np.abs(s_resid).mean(0), v)
@pytest.mark.smoke
def test_summary(self):
np.random.seed(34234)
time = 50 * np.random.uniform(size=200)
status = np.random.randint(0, 2, 200).astype(np.float64)
exog = np.random.normal(size=(200,4))
mod = PHReg(time, exog, status)
rslt = mod.fit()
smry = rslt.summary()
strata = np.kron(np.arange(50), np.ones(4))
mod = PHReg(time, exog, status, strata=strata)
rslt = mod.fit()
smry = rslt.summary()
msg = "3 strata dropped for having no events"
assert_(msg in str(smry))
groups = np.kron(np.arange(25), np.ones(8))
mod = PHReg(time, exog, status)
rslt = mod.fit(groups=groups)
smry = rslt.summary()
entry = np.random.uniform(0.1, 0.8, 200) * time
mod = PHReg(time, exog, status, entry=entry)
rslt = mod.fit()
smry = rslt.summary()
msg = "200 observations have positive entry times"
assert_(msg in str(smry))
@pytest.mark.smoke
def test_predict(self):
# All smoke tests. We should be able to convert the lhr and hr
# tests into real tests against R. There are many options to
# this function that may interact in complicated ways. Only a
# few key combinations are tested here.
np.random.seed(34234)
endog = 50 * np.random.uniform(size=200)
status = np.random.randint(0, 2, 200).astype(np.float64)
exog = np.random.normal(size=(200,4))
mod = PHReg(endog, exog, status)
rslt = mod.fit()
rslt.predict()
for pred_type in 'lhr', 'hr', 'cumhaz', 'surv':
rslt.predict(pred_type=pred_type)
rslt.predict(endog=endog[0:10], pred_type=pred_type)
rslt.predict(endog=endog[0:10], exog=exog[0:10,:],
pred_type=pred_type)
@pytest.mark.smoke
def test_get_distribution(self):
np.random.seed(34234)
n = 200
exog = np.random.normal(size=(n, 2))
lin_pred = exog.sum(1)
elin_pred = np.exp(-lin_pred)
time = -elin_pred * np.log(np.random.uniform(size=n))
status = np.ones(n)
status[0:20] = 0
strata = np.kron(range(5), np.ones(n // 5))
mod = PHReg(time, exog, status=status, strata=strata)
rslt = mod.fit()
dist = rslt.get_distribution()
fitted_means = dist.mean()
true_means = elin_pred
fitted_var = dist.var()
fitted_sd = dist.std()
sample = dist.rvs()
def test_fit_regularized(self):
# Data set sizes
for n,p in (50,2),(100,5):
# Penalty weights
for js,s in enumerate([0,0.1]):
coef_name = "coef_%d_%d_%d" % (n, p, js)
params = getattr(survival_enet_r_results, coef_name)
fname = "survival_data_%d_%d.csv" % (n, p)
time, status, entry, exog = self.load_file(fname)
exog -= exog.mean(0)
exog /= exog.std(0, ddof=1)
model = PHReg(time, exog, status=status, ties='breslow')
sm_result = model.fit_regularized(alpha=s)
# The agreement is not very high, the issue may be on
# the R side. See below for further checks.
assert_allclose(sm_result.params, params, rtol=0.3)
# The penalized log-likelihood that we are maximizing.
def plf(params):
llf = model.loglike(params) / len(time)
L1_wt = 1
llf = llf - s * ((1 - L1_wt)*np.sum(params**2) / 2 + L1_wt*np.sum(np.abs(params)))
return llf
# Confirm that we are doing better than glmnet.
llf_r = plf(params)
llf_sm = plf(sm_result.params)
assert_equal(np.sign(llf_sm - llf_r), 1)
cur_dir = os.path.dirname(os.path.abspath(__file__))
rdir = os.path.join(cur_dir, 'results')
fnames = os.listdir(rdir)
fnames = [x for x in fnames if x.startswith("survival")
and x.endswith(".csv")]
ties = ("breslow", "efron")
entry_f = (False, True)
strata_f = (False, True)
@pytest.mark.parametrize('fname,ties,entry_f,strata_f',
list(itertools.product(fnames, ties, entry_f, strata_f)))
def test_r(fname, ties, entry_f, strata_f):
TestPHReg.do1(fname, ties, entry_f, strata_f)