Add E2E tests (#75)

* add e2e for simple estimators

* Add e2e tests

Author: TomeHirata

tests/test_adjusted_estimator.py

@@ -1,8 +1,72 @@
 import unittest
 import numpy as np
-from sklearn.linear_model import LogisticRegression
+from sklearn.linear_model import LogisticRegression, LinearRegression
 from dte_adj import SimpleLocalDistributionEstimator, AdjustedLocalDistributionEstimator
 
+np.random.seed(123)
+
+
+def generate_data(n=1000, S=4):
+    # Generate W ~ U(0,1)
+    W = np.random.uniform(0, 1, n)
+
+    # Assign strata based on W
+    strata = np.digitize(W, np.linspace(0, 1, S + 1)[1:])
+
+    # Generate X ~ N(0, I_20)
+    X = np.random.randn(n, 20)
+
+    # Treatment assignment Z ~ Bernoulli(0.5) within each stratum
+    Z = np.zeros(n)
+    for s in range(S):
+        indices = np.where(strata == s)[0]
+        Z[indices] = np.random.binomial(1, 0.5, size=len(indices))
+
+    # Define functions b(X, W) and c(X, W)
+    def b(X, W):
+        return (
+            np.sin(np.pi * X[:, 0] * X[:, 1])
+            + 2 * (X[:, 2] - 0.5) ** 2
+            + X[:, 3]
+            + 0.5 * X[:, 4]
+            + 0.1 * W
+        )
+
+    def c(X, W):
+        return 0.1 * (X[:, 0] + np.log(1 + np.exp(X[:, 1])) + W)
+
+    # Define parameters
+    a1, a0 = 4, 1
+    b1, b0 = 1, -1
+    c1, c0 = 3, 3
+
+    # Generate errors
+    epsilon = np.random.randn(n)
+
+    # Compute Y(d)
+    Y0 = a0 + b(X, W) + epsilon
+    Y1 = a1 + b(X, W) + epsilon
+
+    # Compute D(0) and D(1)
+    D0 = (b0 + c(X, W) > c0 * epsilon).astype(int)
+    D1 = np.where(D0 == 0, (b1 + c(X, W) > c1 * epsilon).astype(int), 1)
+
+    # Compute observed D and Y
+    D = D1 * Z + D0 * (1 - Z)
+    Y = Y1 * D + Y0 * (1 - D)
+
+    # discrete
+    Y = np.random.poisson(np.abs(Y))
+
+    return {
+        "W": W,
+        "X": X,
+        "Z": Z,
+        "D": D,
+        "Y": Y,
+        "strata": strata,
+    }
+
 
 class TestLocalEstimators(unittest.TestCase):
     def setUp(self):
@@ -232,3 +296,43 @@ def test_adjusted_local_estimator_predict_lpte(self):
         self.assertTrue(np.all(lower_bound <= upper_bound))
         self.assertTrue(np.all(lower_bound <= beta))
         self.assertTrue(np.all(beta <= upper_bound))
+
+
+class TestE2E(unittest.TestCase):
+    def test_e2e(self):
+        # Arrange
+        data = generate_data(n=3000)
+        X, D, Y, Z, S = data["X"], data["W"], data["Y"], data["Z"], data["strata"]
+        locations = np.array([np.percentile(Y, p) for p in range(10, 91, 10)])
+        simple_estimator = SimpleLocalDistributionEstimator()
+        adjusted_estimator = AdjustedLocalDistributionEstimator(LinearRegression())
+
+        # Act
+        simple_estimator.fit(X, Z, D, Y, S)
+        adjusted_estimator.fit(X, Z, D, Y, S)
+
+        simple_dte, simple_lower_bound, simple_upper_bound = (
+            simple_estimator.predict_dte(1, 0, locations)
+        )
+        adjusted_dte, adjusted_lower_bound, adjusted_upper_bound = (
+            adjusted_estimator.predict_dte(1, 0, locations)
+        )
+
+        # Assert
+        np.testing.assert_(np.all(simple_dte < 0), "Not all values are negative")
+        np.testing.assert_(np.all(adjusted_dte < 0), "Not all values are negative")
+        np.testing.assert_(
+            np.all(simple_lower_bound < simple_upper_bound),
+            "Upper bound is less than lower bound",
+        )
+        np.testing.assert_(
+            np.all(adjusted_lower_bound < adjusted_upper_bound),
+            "Upper bound is less than lower bound",
+        )
+        np.testing.assert_(
+            np.all(
+                adjusted_upper_bound - adjusted_lower_bound
+                < simple_upper_bound - simple_lower_bound
+            ),
+            "Adjusted estimator does not have narrower intervals",
+        )