Updated the introduction

doc/pub/How2ReadData/ipynb/How2ReadData.ipynb

@@ -268,7 +268,7 @@
    "metadata": {},
    "source": [
     "$$\n",
-    "y = 10x+0.01N(0,1),\n",
+    "y = 10x+0.01 \\times N(0,1),\n",
     "$$"
    ]
   },
@@ -283,7 +283,7 @@
     "long run. Here we have only defined the training data and our model, and \n",
     "have not discussed a more rigorous approach to the **cost** function.\n",
     "\n",
-    "We need more rigorous criteria in defining whether we have succeed or\n",
+    "We need more rigorous criteria in defining whether we have succeeded or\n",
     "not in modeling our training data.  You will be surprised to see that\n",
     "many scientists seldomly venture beyond this 'by the eye' approach. A\n",
     "standard approach for the *cost* function is the so-called $\\chi^2$\n",