Fixing small spelling mistake

$lambda$ to $\lambda$

Author: Inconditus

Chapter1_Introduction/Chapter1_Introduction.ipynb

@@ -566,7 +566,7 @@
       "&\\lambda_2 \\sim \\text{Exp}( \\alpha )\n",
       "\\end{align}\n",
       "\n",
-      "$\\alpha$ is called a *hyper-parameter* or *parent variable*. In literal terms, it is a parameter that influences other parameters. Our initial guess at $\\alpha$ does not influence the model too strongly, so we have some flexibility in our choice.  A good rule of thumb is to set the exponential parameter equal to the inverse of the average of the count data. Since we're modeling $\\\\lambda$ using an exponential distribution, we can use the expected value identity shown earlier to get:\n",
+      "$\\alpha$ is called a *hyper-parameter* or *parent variable*. In literal terms, it is a parameter that influences other parameters. Our initial guess at $\\alpha$ does not influence the model too strongly, so we have some flexibility in our choice.  A good rule of thumb is to set the exponential parameter equal to the inverse of the average of the count data. Since we're modeling $\\lambda$ using an exponential distribution, we can use the expected value identity shown earlier to get:\n",
       "\n",
       "$$\\frac{1}{N}\\sum_{i=0}^N \\;C_i \\approx E[\\; \\lambda \\; |\\; \\alpha ] = \\frac{1}{\\alpha}$$ \n",
       "\n",
@@ -1027,4 +1027,4 @@
    "metadata": {}
   }
  ]
-}
+}