diff --git a/Chapter_5_ModelValidationAndSelection/ModelSelection_RealWorldData.ipynb b/Chapter_5_ModelValidationAndSelection/ModelSelection_RealWorldData.ipynb
index d068a16..de3596e 100644
--- a/Chapter_5_ModelValidationAndSelection/ModelSelection_RealWorldData.ipynb
+++ b/Chapter_5_ModelValidationAndSelection/ModelSelection_RealWorldData.ipynb
@@ -818,7 +818,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Increasing the number of trees allows to slighlty increase the Average Precicision and the CP@100. It however has little influence on the AUC ROC, for which 25 trees already provide optimal performances.  "
+    "Increasing the number of trees allows to slightly increase the Average Precicision and the CP@100. It however has little influence on the AUC ROC, for which 25 trees already provide optimal performances.  "
    ]
   },
   {