fix grammar

Author: matheusfacure

causal-inference-for-the-brave-and-true/02-Randomised-Experiments.ipynb

@@ -51,7 +51,7 @@
     "\n",
     "Four months into the crises and many are wondering if the introduced changes could be maintained. There is no question that online learning has its benefits. For once, it is cheaper, since it can save on real estate and transportation. It can also be more digital, leveraging world class content from around the globe, not just from a fixed set of teachers. In spite of all of that, we still need to answer if online learning has or not a negative or positive impact in the student's academic performance.\n",
     "\n",
-    "One way to answer this is to take students from schools that give mostly online classes and compare them with students from schools that give lectures in traditional classrooms. As we know by now this is not the best approach. It could be that online schools attract only the well disciplined students that do better than average even if the class where presential. In this case, we would have a positive bias, where the treated are academically better than the untreated: \\\\(E[Y_0|T=1] > E[Y_0|T=0]\\\\).\n",
+    "One way to answer this is to take students from schools that give mostly online classes and compare them with students from schools that give lectures in traditional classrooms. As we know by now this is not the best approach. It could be that online schools attract only the well disciplined students that do better than average even if the class were presential. In this case, we would have a positive bias, where the treated are academically better than the untreated: \\\\(E[Y_0|T=1] > E[Y_0|T=0]\\\\).\n",
     "\n",
     "Or, on the flip side, it could be that online classes are cheaper and are composed mostly of less wealthy students, who might have to work besides studying. In this case, these students would do worse than those from the presidential schools even if they took presential classes. If this was the case, we would have bias in the other direction, where the treated are academically worse than the untreated:  \\\\(E[Y_0|T=1] < E[Y_0|T=0]\\\\). \n",
     "\n",
@@ -422,7 +422,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.8.5"
+   "version": "3.6.9"
   }
  },
  "nbformat": 4,