fix notebook and typo in did model

Author: SvenKlaassen

doc/examples/py_double_ml_did.ipynb

@@ -164,7 +164,7 @@
    "outputs": [],
    "source": [
     "n_rep = 200\n",
-    "ATTE = 0\n",
+    "ATTE = 0.0\n",
     "\n",
     "ATTE_estimates = np.full((n_rep), np.nan)\n",
     "coverage = np.full((n_rep), np.nan)\n",
@@ -181,7 +181,7 @@
     "\n",
     "    ATTE_estimates[i_rep] = dml_did.coef\n",
     "    confint = dml_did.confint(level=0.95)\n",
-    "    coverage [i_rep] = (confint['2.5 %'] < ATTE) & (ATTE < confint['97.5 %'])\n",
+    "    coverage [i_rep] = (confint['2.5 %'] <= ATTE) & (ATTE <= confint['97.5 %'])\n",
     "    ci_length[i_rep] = confint['97.5 %'] - confint['2.5 %']"
    ]
   },
@@ -367,7 +367,7 @@
    "outputs": [],
    "source": [
     "n_rep = 200\n",
-    "ATTE = 0\n",
+    "ATTE = 0.0\n",
     "\n",
     "ATTE_estimates = np.full((n_rep), np.nan)\n",
     "coverage = np.full((n_rep), np.nan)\n",
@@ -384,7 +384,7 @@
     "\n",
     "    ATTE_estimates[i_rep] = dml_did.coef\n",
     "    confint = dml_did.confint(level=0.95)\n",
-    "    coverage [i_rep] = (confint['2.5 %'] < ATTE) & (ATTE < confint['97.5 %'])\n",
+    "    coverage [i_rep] = (confint['2.5 %'] <= ATTE) & (ATTE <= confint['97.5 %'])\n",
     "    ci_length[i_rep] = confint['97.5 %'] - confint['2.5 %']"
    ]
   },
@@ -450,7 +450,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.11.2"
+   "version": "3.10.10"
   },
   "orig_nbformat": 4,
   "vscode": {

doc/shared/models/did.rst

@@ -6,7 +6,7 @@ let :math:`Y_{it}` be the outcome of interest for unit :math:`i` at time :math:`
 if unit :math:`i` is treated before time :math:`t` (otherwise :math:`D_{it}=0`). Since all units start as untreated (:math:`D_{i0}=0`), define 
 :math:`D_{i}=D_{i1}.` Relying on the potential outcome notation, denote :math:`Y_{it}(0)` as the outcome of unit :math:`i` at time :math:`t` if the unit did not receive 
 treatment up until time :math:`t` and analogously for :math:`Y_{it}(1)` with treatment. Consequently, the observed outcome 
-for unit is :math:`i` at time :math:`t` is :math:`Y_{it}=D_i Y_{it}(1) + (1-D_i) Y_{it}(0)`. Further, let 
+for unit is :math:`i` at time :math:`t` is :math:`Y_{it}=D_{it} Y_{it}(1) + (1-D_{it}) Y_{it}(0)`. Further, let 
 :math:`X_i` be a vector of pre-treatment covariates.
 
 Target parameter of interest is the average treatment effect on the treated (ATTE)