diff --git a/doc/pub/week37/html/._week37-bs005.html b/doc/pub/week37/html/._week37-bs005.html
index 68415a18b..f77538205 100644
--- a/doc/pub/week37/html/._week37-bs005.html
+++ b/doc/pub/week37/html/._week37-bs005.html
@@ -359,7 +359,7 @@ X \equiv \begin{bmatrix}
 \end{bmatrix}.
 $$
 
-<p>The cost/loss/risk function is given by (</p>
+<p>The cost/loss/risk function is given by </p>
 $$
 C(\theta) = \frac{1}{n}||X\theta-\mathbf{y}||_{2}^{2} = \frac{1}{n}\sum_{i=1}^{100}\left[ (\theta_0 + \theta_1 x_i)^2 - 2 y_i (\theta_0 + \theta_1 x_i) + y_i^2\right] 
 $$
diff --git a/doc/pub/week37/html/week37-reveal.html b/doc/pub/week37/html/week37-reveal.html
index 841138031..f3b1b54e5 100644
--- a/doc/pub/week37/html/week37-reveal.html
+++ b/doc/pub/week37/html/week37-reveal.html
@@ -304,7 +304,7 @@ X \equiv \begin{bmatrix}
 $$
 <p>&nbsp;<br>
 
-<p>The cost/loss/risk function is given by (</p>
+<p>The cost/loss/risk function is given by </p>
 <p>&nbsp;<br>
 $$
 C(\theta) = \frac{1}{n}||X\theta-\mathbf{y}||_{2}^{2} = \frac{1}{n}\sum_{i=1}^{100}\left[ (\theta_0 + \theta_1 x_i)^2 - 2 y_i (\theta_0 + \theta_1 x_i) + y_i^2\right] 
diff --git a/doc/pub/week37/html/week37-solarized.html b/doc/pub/week37/html/week37-solarized.html
index 07225dd2c..154aa4505 100644
--- a/doc/pub/week37/html/week37-solarized.html
+++ b/doc/pub/week37/html/week37-solarized.html
@@ -405,7 +405,7 @@ X \equiv \begin{bmatrix}
 \end{bmatrix}.
 $$
 
-<p>The cost/loss/risk function is given by (</p>
+<p>The cost/loss/risk function is given by </p>
 $$
 C(\theta) = \frac{1}{n}||X\theta-\mathbf{y}||_{2}^{2} = \frac{1}{n}\sum_{i=1}^{100}\left[ (\theta_0 + \theta_1 x_i)^2 - 2 y_i (\theta_0 + \theta_1 x_i) + y_i^2\right] 
 $$
diff --git a/doc/pub/week37/html/week37.html b/doc/pub/week37/html/week37.html
index a24a65f19..59ee554dd 100644
--- a/doc/pub/week37/html/week37.html
+++ b/doc/pub/week37/html/week37.html
@@ -482,7 +482,7 @@ X \equiv \begin{bmatrix}
 \end{bmatrix}.
 $$
 
-<p>The cost/loss/risk function is given by (</p>
+<p>The cost/loss/risk function is given by </p>
 $$
 C(\theta) = \frac{1}{n}||X\theta-\mathbf{y}||_{2}^{2} = \frac{1}{n}\sum_{i=1}^{100}\left[ (\theta_0 + \theta_1 x_i)^2 - 2 y_i (\theta_0 + \theta_1 x_i) + y_i^2\right] 
 $$
diff --git a/doc/pub/week37/ipynb/ipynb-week37-src.tar.gz b/doc/pub/week37/ipynb/ipynb-week37-src.tar.gz
index 56a733323..5b5b01684 100644
Binary files a/doc/pub/week37/ipynb/ipynb-week37-src.tar.gz and b/doc/pub/week37/ipynb/ipynb-week37-src.tar.gz differ
diff --git a/doc/pub/week37/ipynb/week37.ipynb b/doc/pub/week37/ipynb/week37.ipynb
index eb66de6d4..6ec95c3cd 100644
--- a/doc/pub/week37/ipynb/week37.ipynb
+++ b/doc/pub/week37/ipynb/week37.ipynb
@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "markdown",
-   "id": "50812059",
+   "id": "4f3beaf1",
    "metadata": {
     "editable": true
    },
@@ -14,7 +14,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7793a9e0",
+   "id": "46fe6a26",
    "metadata": {
     "editable": true
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@@ -29,7 +29,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a3583f46",
+   "id": "f7c7fee9",
    "metadata": {
     "editable": true
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@@ -52,7 +52,7 @@
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   {
    "cell_type": "markdown",
-   "id": "aeab1b07",
+   "id": "29a5df4a",
    "metadata": {
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@@ -69,7 +69,7 @@
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   {
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-   "id": "113b8927",
+   "id": "d1cabb8b",
    "metadata": {
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@@ -79,7 +79,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d6aea694",
+   "id": "c1499668",
    "metadata": {
     "editable": true
    },
@@ -103,7 +103,7 @@
   {
    "cell_type": "code",
    "execution_count": 1,
-   "id": "4ac32eb7",
+   "id": "8f93b870",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -117,7 +117,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e4d1a33d",
+   "id": "cafa88bc",
    "metadata": {
     "editable": true
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@@ -128,7 +128,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c4c6aadb",
+   "id": "d46f9bbc",
    "metadata": {
     "editable": true
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@@ -140,7 +140,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "211ddc94",
+   "id": "c6860f97",
    "metadata": {
     "editable": true
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@@ -150,7 +150,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "264d3a45",
+   "id": "5961000b",
    "metadata": {
     "editable": true
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@@ -162,7 +162,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2f40241b",
+   "id": "602cdea2",
    "metadata": {
     "editable": true
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@@ -176,7 +176,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1bf35a52",
+   "id": "2a6ab00e",
    "metadata": {
     "editable": true
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@@ -192,17 +192,17 @@
   },
   {
    "cell_type": "markdown",
-   "id": "44613300",
+   "id": "f9fb9a51",
    "metadata": {
     "editable": true
    },
    "source": [
-    "The cost/loss/risk function is given by ("
+    "The cost/loss/risk function is given by"
    ]
   },
   {
    "cell_type": "markdown",
-   "id": "438523f1",
+   "id": "a2f3adf9",
    "metadata": {
     "editable": true
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@@ -214,7 +214,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f0e7f06b",
+   "id": "e4cffe8e",
    "metadata": {
     "editable": true
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@@ -224,7 +224,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ff2b1f63",
+   "id": "3ebf7860",
    "metadata": {
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@@ -236,7 +236,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6a100c53",
+   "id": "f8cdd774",
    "metadata": {
     "editable": true
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@@ -250,7 +250,7 @@
   },
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    "cell_type": "markdown",
-   "id": "322be116",
+   "id": "67a028fe",
    "metadata": {
     "editable": true
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@@ -260,7 +260,7 @@
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    "cell_type": "markdown",
-   "id": "78435579",
+   "id": "28b34be8",
    "metadata": {
     "editable": true
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@@ -271,7 +271,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "bc7776c0",
+   "id": "7068c946",
    "metadata": {
     "editable": true
    },
@@ -286,7 +286,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a10aa000",
+   "id": "289d7cf9",
    "metadata": {
     "editable": true
    },
@@ -296,7 +296,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b52074ac",
+   "id": "3bacfa14",
    "metadata": {
     "editable": true
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@@ -308,7 +308,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "91581f81",
+   "id": "16c159ac",
    "metadata": {
     "editable": true
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@@ -320,7 +320,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4416c640",
+   "id": "cf04e4b0",
    "metadata": {
     "editable": true
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@@ -335,7 +335,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ea0cefb8",
+   "id": "0d9644f3",
    "metadata": {
     "editable": true
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@@ -348,7 +348,7 @@
   {
    "cell_type": "code",
    "execution_count": 2,
-   "id": "61693bed",
+   "id": "33a70e79",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -407,7 +407,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "648a50c5",
+   "id": "85b9190b",
    "metadata": {
     "editable": true
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@@ -419,7 +419,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b2705e40",
+   "id": "c6bf4720",
    "metadata": {
     "editable": true
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@@ -431,7 +431,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0b1d169a",
+   "id": "8f766543",
    "metadata": {
     "editable": true
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@@ -441,7 +441,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "151c7c6a",
+   "id": "31c687f3",
    "metadata": {
     "editable": true
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@@ -455,7 +455,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "40aa26f3",
+   "id": "ff33ba55",
    "metadata": {
     "editable": true
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@@ -465,7 +465,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e4016061",
+   "id": "02d68d7d",
    "metadata": {
     "editable": true
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@@ -477,7 +477,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7fa28627",
+   "id": "aee5a999",
    "metadata": {
     "editable": true
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@@ -488,7 +488,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "97e1c1a8",
+   "id": "d4c6e860",
    "metadata": {
     "editable": true
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@@ -503,7 +503,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "40e8f9a6",
+   "id": "d0b1ab36",
    "metadata": {
     "editable": true
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@@ -517,7 +517,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "627e04e5",
+   "id": "feffa94a",
    "metadata": {
     "editable": true
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@@ -528,7 +528,7 @@
   {
    "cell_type": "code",
    "execution_count": 3,
-   "id": "33ea2bc1",
+   "id": "17b7aebb",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -589,7 +589,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d4f9401f",
+   "id": "845d5551",
    "metadata": {
     "editable": true
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@@ -611,7 +611,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "bb52c3f1",
+   "id": "55818d27",
    "metadata": {
     "editable": true
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@@ -626,7 +626,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e0b7af14",
+   "id": "bdfa4705",
    "metadata": {
     "editable": true
    },
@@ -637,7 +637,7 @@
   {
    "cell_type": "code",
    "execution_count": 4,
-   "id": "a3ec834a",
+   "id": "b13373bb",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -703,7 +703,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1d1552c1",
+   "id": "01f07f3c",
    "metadata": {
     "editable": true
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@@ -714,7 +714,7 @@
   {
    "cell_type": "code",
    "execution_count": 5,
-   "id": "4d263b16",
+   "id": "dd296802",
    "metadata": {
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     "editable": true
@@ -788,7 +788,7 @@
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   {
    "cell_type": "markdown",
-   "id": "e04acafb",
+   "id": "2b995d39",
    "metadata": {
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@@ -807,7 +807,7 @@
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   {
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-   "id": "a51bbde0",
+   "id": "ec3098ab",
    "metadata": {
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@@ -828,7 +828,7 @@
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   {
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-   "id": "b63bb5be",
+   "id": "ae3c5061",
    "metadata": {
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@@ -844,7 +844,7 @@
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   {
    "cell_type": "markdown",
-   "id": "7fc69be3",
+   "id": "54028ccc",
    "metadata": {
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@@ -858,7 +858,7 @@
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   {
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-   "id": "ff9e2f5b",
+   "id": "17875f98",
    "metadata": {
     "editable": true
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@@ -886,7 +886,7 @@
   },
   {
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-   "id": "551735b2",
+   "id": "40862db0",
    "metadata": {
     "editable": true
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@@ -918,7 +918,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "aaea617e",
+   "id": "075431a2",
    "metadata": {
     "editable": true
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@@ -935,7 +935,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7072bd4a",
+   "id": "65dcd718",
    "metadata": {
     "editable": true
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@@ -948,7 +948,7 @@
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   {
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-   "id": "321840eb",
+   "id": "ccf20bf2",
    "metadata": {
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@@ -961,7 +961,7 @@
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   {
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+   "id": "7cf7a667",
    "metadata": {
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@@ -974,7 +974,7 @@
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   {
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-   "id": "66a000dd",
+   "id": "21eeb773",
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@@ -988,7 +988,7 @@
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   {
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+   "id": "562bbf59",
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@@ -1010,7 +1010,7 @@
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@@ -1025,7 +1025,7 @@
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   {
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+   "id": "4cd95b23",
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@@ -1037,7 +1037,7 @@
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   {
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+   "id": "ea4324e1",
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@@ -1050,7 +1050,7 @@
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+   "id": "5287666c",
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@@ -1064,7 +1064,7 @@
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+   "id": "596acab8",
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@@ -1075,7 +1075,7 @@
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-   "id": "8ab6969d",
+   "id": "3b4d8b03",
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@@ -1100,7 +1100,7 @@
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@@ -1116,7 +1116,7 @@
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@@ -1137,7 +1137,7 @@
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@@ -1157,7 +1157,7 @@
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@@ -1176,7 +1176,7 @@
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@@ -1211,7 +1211,7 @@
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@@ -1224,7 +1224,7 @@
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-   "id": "0951608f",
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@@ -1301,7 +1301,7 @@
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@@ -1316,7 +1316,7 @@
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@@ -1347,7 +1347,7 @@
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@@ -1369,7 +1369,7 @@
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@@ -1389,7 +1389,7 @@
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@@ -1405,7 +1405,7 @@
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@@ -1425,7 +1425,7 @@
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@@ -1437,7 +1437,7 @@
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@@ -1449,7 +1449,7 @@
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@@ -1461,7 +1461,7 @@
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@@ -1473,7 +1473,7 @@
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@@ -1484,7 +1484,7 @@
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@@ -1496,7 +1496,7 @@
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@@ -1506,7 +1506,7 @@
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@@ -1518,7 +1518,7 @@
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@@ -1528,7 +1528,7 @@
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@@ -1549,7 +1549,7 @@
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    "metadata": {
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    },
@@ -1562,7 +1562,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "8e05a132",
+   "id": "b5808edc",
    "metadata": {
     "editable": true
    },
@@ -1574,7 +1574,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "27a9e5c9",
+   "id": "c36f305f",
    "metadata": {
     "editable": true
    },
@@ -1591,7 +1591,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "897391da",
+   "id": "6e4679b3",
    "metadata": {
     "editable": true
    },
@@ -1607,7 +1607,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "28fccc5b",
+   "id": "d58547fa",
    "metadata": {
     "editable": true
    },
@@ -1629,7 +1629,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6843042b",
+   "id": "6989903c",
    "metadata": {
     "editable": true
    },
@@ -1647,7 +1647,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4c5e2e6d",
+   "id": "a58fbe05",
    "metadata": {
     "editable": true
    },
@@ -1667,7 +1667,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ce71b8ba",
+   "id": "98700cff",
    "metadata": {
     "editable": true
    },
@@ -1681,7 +1681,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d5666bf4",
+   "id": "e55261d4",
    "metadata": {
     "editable": true
    },
@@ -1693,7 +1693,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "564bb697",
+   "id": "64676960",
    "metadata": {
     "editable": true
    },
@@ -1705,7 +1705,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1589c6f3",
+   "id": "1e3007bd",
    "metadata": {
     "editable": true
    },
@@ -1717,7 +1717,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "72ee2d0a",
+   "id": "5df06a58",
    "metadata": {
     "editable": true
    },
@@ -1729,7 +1729,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3d03c54f",
+   "id": "034cb12a",
    "metadata": {
     "editable": true
    },
@@ -1740,7 +1740,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4ff05e26",
+   "id": "429a18be",
    "metadata": {
     "editable": true
    },
@@ -1752,7 +1752,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7629b25b",
+   "id": "1672b4fd",
    "metadata": {
     "editable": true
    },
@@ -1766,7 +1766,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "91889f1c",
+   "id": "dba6d945",
    "metadata": {
     "editable": true
    },
@@ -1777,7 +1777,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "de09f733",
+   "id": "13db1c10",
    "metadata": {
     "editable": true
    },
@@ -1789,7 +1789,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d2ec1c97",
+   "id": "e30b02ab",
    "metadata": {
     "editable": true
    },
@@ -1811,7 +1811,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "37b4758a",
+   "id": "5ac8ae68",
    "metadata": {
     "editable": true
    },
@@ -1835,7 +1835,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d75712f4",
+   "id": "86abec40",
    "metadata": {
     "editable": true
    },
@@ -1851,7 +1851,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e5041844",
+   "id": "448ff439",
    "metadata": {
     "editable": true
    },
@@ -1867,7 +1867,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "00e66b1d",
+   "id": "86183049",
    "metadata": {
     "editable": true
    },
@@ -1881,7 +1881,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "83d5a029",
+   "id": "78a7d51b",
    "metadata": {
     "editable": true
    },
@@ -1899,7 +1899,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "723bf8b1",
+   "id": "0b0e62b6",
    "metadata": {
     "editable": true
    },
@@ -1920,7 +1920,7 @@
   {
    "cell_type": "code",
    "execution_count": 9,
-   "id": "4c5339d0",
+   "id": "d19005f0",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -1980,7 +1980,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "96801735",
+   "id": "4f7fa973",
    "metadata": {
     "editable": true
    },
@@ -1991,7 +1991,7 @@
   {
    "cell_type": "code",
    "execution_count": 10,
-   "id": "ea189034",
+   "id": "34cb0de4",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2055,7 +2055,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "68e93f81",
+   "id": "4cb35cee",
    "metadata": {
     "editable": true
    },
@@ -2070,7 +2070,7 @@
   {
    "cell_type": "code",
    "execution_count": 11,
-   "id": "bbb479a7",
+   "id": "74934aab",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2154,7 +2154,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "37b1e945",
+   "id": "d8ee3d35",
    "metadata": {
     "editable": true
    },
@@ -2165,7 +2165,7 @@
   {
    "cell_type": "code",
    "execution_count": 12,
-   "id": "59d8c89a",
+   "id": "63184f2b",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2243,7 +2243,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "19ff08d8",
+   "id": "c44ce795",
    "metadata": {
     "editable": true
    },
@@ -2256,7 +2256,7 @@
   {
    "cell_type": "code",
    "execution_count": 13,
-   "id": "b9373caf",
+   "id": "74e118d6",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2300,7 +2300,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ebb24d8f",
+   "id": "3789172e",
    "metadata": {
     "editable": true
    },
@@ -2311,7 +2311,7 @@
   {
    "cell_type": "code",
    "execution_count": 14,
-   "id": "921bd177",
+   "id": "5152d211",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2370,7 +2370,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "789528fb",
+   "id": "34e87757",
    "metadata": {
     "editable": true
    },
@@ -2380,7 +2380,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d3eee3bd",
+   "id": "713154cb",
    "metadata": {
     "editable": true
    },
@@ -2391,7 +2391,7 @@
   {
    "cell_type": "code",
    "execution_count": 15,
-   "id": "9c483eda",
+   "id": "3e863305",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2456,7 +2456,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "18713b46",
+   "id": "a5fa4647",
    "metadata": {
     "editable": true
    },
@@ -2467,7 +2467,7 @@
   {
    "cell_type": "code",
    "execution_count": 16,
-   "id": "f867cb1a",
+   "id": "0b318139",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2537,7 +2537,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "700401c6",
+   "id": "967dd1d1",
    "metadata": {
     "editable": true
    },
@@ -2554,7 +2554,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "9a76e50d",
+   "id": "ad137d49",
    "metadata": {
     "editable": true
    },
@@ -2582,7 +2582,7 @@
   {
    "cell_type": "code",
    "execution_count": 17,
-   "id": "d00e0f77",
+   "id": "8a6c2cb4",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2602,7 +2602,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5236f9a5",
+   "id": "76bf3c81",
    "metadata": {
     "editable": true
    },
@@ -2618,7 +2618,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c05d7dc6",
+   "id": "818c6d58",
    "metadata": {
     "editable": true
    },
@@ -2638,7 +2638,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7b7b6cf3",
+   "id": "58481e8f",
    "metadata": {
     "editable": true
    },
@@ -2665,7 +2665,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6c08d35c",
+   "id": "4e94a32c",
    "metadata": {
     "editable": true
    },
@@ -2678,7 +2678,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2eb821a9",
+   "id": "3a93bb3e",
    "metadata": {
     "editable": true
    },
@@ -2690,7 +2690,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "9a960d29",
+   "id": "c603fb31",
    "metadata": {
     "editable": true
    },
@@ -2705,7 +2705,7 @@
   {
    "cell_type": "code",
    "execution_count": 18,
-   "id": "57504163",
+   "id": "363ae494",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2732,7 +2732,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4a431690",
+   "id": "429b71ce",
    "metadata": {
     "editable": true
    },
@@ -2746,7 +2746,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b3010e14",
+   "id": "ec3c7657",
    "metadata": {
     "editable": true
    },
@@ -2758,7 +2758,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "96f0d6df",
+   "id": "c6c2fd1d",
    "metadata": {
     "editable": true
    },
@@ -2775,7 +2775,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "46d0d2a1",
+   "id": "1141934f",
    "metadata": {
     "editable": true
    },
@@ -2787,7 +2787,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3a2eda90",
+   "id": "efc84979",
    "metadata": {
     "editable": true
    },
@@ -2797,7 +2797,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1191e11c",
+   "id": "6be29872",
    "metadata": {
     "editable": true
    },
@@ -2809,7 +2809,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "fe46dfdd",
+   "id": "8f128adc",
    "metadata": {
     "editable": true
    },
@@ -2819,7 +2819,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "86deeaa9",
+   "id": "967b009a",
    "metadata": {
     "editable": true
    },
@@ -2831,7 +2831,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "525ee0f5",
+   "id": "181e0b18",
    "metadata": {
     "editable": true
    },
@@ -2842,7 +2842,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0bc83987",
+   "id": "6fe29ace",
    "metadata": {
     "editable": true
    },
@@ -2854,7 +2854,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "574751fd",
+   "id": "795a350c",
    "metadata": {
     "editable": true
    },
@@ -2864,7 +2864,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0326f019",
+   "id": "9a0ebe42",
    "metadata": {
     "editable": true
    },
@@ -2876,7 +2876,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4d7402c2",
+   "id": "800ad4c7",
    "metadata": {
     "editable": true
    },
@@ -2886,7 +2886,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3f3155bf",
+   "id": "4ed44194",
    "metadata": {
     "editable": true
    },
@@ -2898,7 +2898,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7159445b",
+   "id": "f6fc455e",
    "metadata": {
     "editable": true
    },
@@ -2908,7 +2908,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "9eef8c8c",
+   "id": "1d434e5d",
    "metadata": {
     "editable": true
    },
@@ -2920,7 +2920,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a0e96ef0",
+   "id": "011d7385",
    "metadata": {
     "editable": true
    },
@@ -2930,7 +2930,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "cc17d03f",
+   "id": "9bb92755",
    "metadata": {
     "editable": true
    },
@@ -2942,7 +2942,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "99988d41",
+   "id": "7287a085",
    "metadata": {
     "editable": true
    },
@@ -2952,7 +2952,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5f9a2a05",
+   "id": "1ebd1481",
    "metadata": {
     "editable": true
    },
@@ -2964,7 +2964,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4c0b0b11",
+   "id": "01da7453",
    "metadata": {
     "editable": true
    },
@@ -2974,7 +2974,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "77243441",
+   "id": "2719429f",
    "metadata": {
     "editable": true
    },
@@ -2986,7 +2986,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6647833f",
+   "id": "1b7a1119",
    "metadata": {
     "editable": true
    },
@@ -2996,7 +2996,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3f9dbf20",
+   "id": "5455e569",
    "metadata": {
     "editable": true
    },
@@ -3008,7 +3008,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3290cd69",
+   "id": "82719ade",
    "metadata": {
     "editable": true
    },
@@ -3020,7 +3020,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "400b3a14",
+   "id": "d87ce00b",
    "metadata": {
     "editable": true
    },
@@ -3032,7 +3032,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0321f9fe",
+   "id": "aad7612a",
    "metadata": {
     "editable": true
    },
@@ -3042,7 +3042,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "955ed99b",
+   "id": "3c7ca158",
    "metadata": {
     "editable": true
    },
@@ -3054,7 +3054,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f080e69a",
+   "id": "b5c113ba",
    "metadata": {
     "editable": true
    },
@@ -3067,7 +3067,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a7ff8bf8",
+   "id": "aad866d0",
    "metadata": {
     "editable": true
    },
@@ -3079,7 +3079,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "89a9d63b",
+   "id": "a4e7459d",
    "metadata": {
     "editable": true
    },
@@ -3093,7 +3093,7 @@
   {
    "cell_type": "code",
    "execution_count": 19,
-   "id": "2f17916c",
+   "id": "2af50ed1",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -3190,7 +3190,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "938e24aa",
+   "id": "e468f434",
    "metadata": {
     "editable": true
    },
@@ -3211,7 +3211,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e3979f55",
+   "id": "0daaeb51",
    "metadata": {
     "editable": true
    },
@@ -3223,7 +3223,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2ffb16fe",
+   "id": "29f1ae2a",
    "metadata": {
     "editable": true
    },
@@ -3233,7 +3233,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "417d919e",
+   "id": "133f65de",
    "metadata": {
     "editable": true
    },
@@ -3245,7 +3245,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "dbb044d9",
+   "id": "b5f4350c",
    "metadata": {
     "editable": true
    },
@@ -3255,7 +3255,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "39ac3a58",
+   "id": "1f6fc172",
    "metadata": {
     "editable": true
    },
@@ -3267,7 +3267,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "839d8c1f",
+   "id": "c5afa388",
    "metadata": {
     "editable": true
    },
@@ -3285,7 +3285,7 @@
   {
    "cell_type": "code",
    "execution_count": 20,
-   "id": "1a39a394",
+   "id": "5718b4ec",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -3361,7 +3361,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "20df8406",
+   "id": "5e7c8319",
    "metadata": {
     "editable": true
    },
@@ -3375,7 +3375,7 @@
   {
    "cell_type": "code",
    "execution_count": 21,
-   "id": "688f0a26",
+   "id": "3b7f797a",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -3464,7 +3464,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "fea0581c",
+   "id": "5e9da20b",
    "metadata": {
     "editable": true
    },
diff --git a/doc/src/week37/week37.do.txt b/doc/src/week37/week37.do.txt
index 80220d91b..ad4252412 100644
--- a/doc/src/week37/week37.do.txt
+++ b/doc/src/week37/week37.do.txt
@@ -84,7 +84,7 @@ X \equiv \begin{bmatrix}
 \end{bmatrix}.
 \]
 !et
-The cost/loss/risk function is given by (
+The cost/loss/risk function is given by 
 !bt
 \[
 C(\theta) = \frac{1}{n}||X\theta-\mathbf{y}||_{2}^{2} = \frac{1}{n}\sum_{i=1}^{100}\left[ (\theta_0 + \theta_1 x_i)^2 - 2 y_i (\theta_0 + \theta_1 x_i) + y_i^2\right]