diff --git a/doc/pub/week37/html/._week37-bs017.html b/doc/pub/week37/html/._week37-bs017.html
index eb087cb9c..85840d3d6 100644
--- a/doc/pub/week37/html/._week37-bs017.html
+++ b/doc/pub/week37/html/._week37-bs017.html
@@ -310,13 +310,13 @@ constants terms that do not depend on \( \beta \), we have
 </p>
 
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 
 <p>and replacing \( 1/\tau \) with \( \lambda \) we have</p>
 
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 
 <p>which is our Lasso cost function!  </p>
diff --git a/doc/pub/week37/html/week37-reveal.html b/doc/pub/week37/html/week37-reveal.html
index ed598f6d3..8507903d8 100644
--- a/doc/pub/week37/html/week37-reveal.html
+++ b/doc/pub/week37/html/week37-reveal.html
@@ -652,7 +652,7 @@ constants terms that do not depend on \( \beta \), we have
 
 <p>&nbsp;<br>
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 <p>&nbsp;<br>
 
@@ -660,7 +660,7 @@ $$
 
 <p>&nbsp;<br>
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 <p>&nbsp;<br>
 
diff --git a/doc/pub/week37/html/week37-solarized.html b/doc/pub/week37/html/week37-solarized.html
index 5a13d9675..8ffb0cd00 100644
--- a/doc/pub/week37/html/week37-solarized.html
+++ b/doc/pub/week37/html/week37-solarized.html
@@ -636,13 +636,13 @@ constants terms that do not depend on \( \beta \), we have
 </p>
 
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 
 <p>and replacing \( 1/\tau \) with \( \lambda \) we have</p>
 
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 
 <p>which is our Lasso cost function!  </p>
diff --git a/doc/pub/week37/html/week37.html b/doc/pub/week37/html/week37.html
index 93e88c43a..10a79eecd 100644
--- a/doc/pub/week37/html/week37.html
+++ b/doc/pub/week37/html/week37.html
@@ -713,13 +713,13 @@ constants terms that do not depend on \( \beta \), we have
 </p>
 
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 
 <p>and replacing \( 1/\tau \) with \( \lambda \) we have</p>
 
 $$
-C(\boldsymbol{\beta}=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
+C(\boldsymbol{\beta})=\frac{\vert\vert (\boldsymbol{y}-\boldsymbol{X}\boldsymbol{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\boldsymbol{\beta}\vert\vert_1,
 $$
 
 <p>which is our Lasso cost function!  </p>
diff --git a/doc/pub/week37/ipynb/ipynb-week37-src.tar.gz b/doc/pub/week37/ipynb/ipynb-week37-src.tar.gz
index 5a8c788c4..f5a3d4866 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 c24beccbd..2281efc10 100644
--- a/doc/pub/week37/ipynb/week37.ipynb
+++ b/doc/pub/week37/ipynb/week37.ipynb
@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "markdown",
-   "id": "7c0ddab1",
+   "id": "1abc3180",
    "metadata": {
     "editable": true
    },
@@ -14,7 +14,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6c033bf4",
+   "id": "c1daea13",
    "metadata": {
     "editable": true
    },
@@ -29,7 +29,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e4cd5fa1",
+   "id": "44f3b13a",
    "metadata": {
     "editable": true
    },
@@ -59,7 +59,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "bf80a276",
+   "id": "9bfba57b",
    "metadata": {
     "editable": true
    },
@@ -81,7 +81,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0e1f0a90",
+   "id": "bb5184fb",
    "metadata": {
     "editable": true
    },
@@ -91,7 +91,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1b290d64",
+   "id": "fe16ef77",
    "metadata": {
     "editable": true
    },
@@ -114,7 +114,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ceed3a82",
+   "id": "16407da5",
    "metadata": {
     "editable": true
    },
@@ -126,7 +126,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1d7e8f98",
+   "id": "7259f755",
    "metadata": {
     "editable": true
    },
@@ -139,7 +139,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "58722d7d",
+   "id": "8197a563",
    "metadata": {
     "editable": true
    },
@@ -151,7 +151,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "45120edc",
+   "id": "55178ede",
    "metadata": {
     "editable": true
    },
@@ -163,7 +163,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4f3b680a",
+   "id": "8df6cfdc",
    "metadata": {
     "editable": true
    },
@@ -175,7 +175,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "08489797",
+   "id": "725df6b0",
    "metadata": {
     "editable": true
    },
@@ -186,7 +186,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a1c81f06",
+   "id": "32b0c74a",
    "metadata": {
     "editable": true
    },
@@ -198,7 +198,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4e092776",
+   "id": "40512d38",
    "metadata": {
     "editable": true
    },
@@ -209,7 +209,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "79e5358a",
+   "id": "1867bac9",
    "metadata": {
     "editable": true
    },
@@ -221,7 +221,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e5a4f865",
+   "id": "d5d17026",
    "metadata": {
     "editable": true
    },
@@ -231,7 +231,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "10b81ba7",
+   "id": "70980886",
    "metadata": {
     "editable": true
    },
@@ -262,7 +262,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3349cb27",
+   "id": "e2f951bb",
    "metadata": {
     "editable": true
    },
@@ -274,7 +274,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0fd1502e",
+   "id": "85dbdab8",
    "metadata": {
     "editable": true
    },
@@ -286,7 +286,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "43cba0e8",
+   "id": "bcfb3f71",
    "metadata": {
     "editable": true
    },
@@ -296,7 +296,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d6f4e7dc",
+   "id": "e59b8708",
    "metadata": {
     "editable": true
    },
@@ -308,7 +308,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "50c2d673",
+   "id": "80d942c3",
    "metadata": {
     "editable": true
    },
@@ -318,7 +318,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "30315a10",
+   "id": "45e5df6c",
    "metadata": {
     "editable": true
    },
@@ -330,7 +330,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "fd8cdf51",
+   "id": "0f759ec1",
    "metadata": {
     "editable": true
    },
@@ -340,7 +340,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7323296b",
+   "id": "18e4dc4b",
    "metadata": {
     "editable": true
    },
@@ -352,7 +352,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e21334ab",
+   "id": "b50c9cf8",
    "metadata": {
     "editable": true
    },
@@ -362,7 +362,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "82974124",
+   "id": "9c043888",
    "metadata": {
     "editable": true
    },
@@ -382,7 +382,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e053e43c",
+   "id": "936f4f77",
    "metadata": {
     "editable": true
    },
@@ -394,7 +394,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "94098e13",
+   "id": "306274ee",
    "metadata": {
     "editable": true
    },
@@ -404,7 +404,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "27625b1f",
+   "id": "581c5f93",
    "metadata": {
     "editable": true
    },
@@ -416,7 +416,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "8f3cc8b4",
+   "id": "40a1da92",
    "metadata": {
     "editable": true
    },
@@ -428,7 +428,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d7d5464d",
+   "id": "f030b59d",
    "metadata": {
     "editable": true
    },
@@ -440,7 +440,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c292afee",
+   "id": "1f7cab98",
    "metadata": {
     "editable": true
    },
@@ -452,7 +452,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "cdbbd444",
+   "id": "e1446472",
    "metadata": {
     "editable": true
    },
@@ -464,7 +464,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "100a8014",
+   "id": "92ddfccf",
    "metadata": {
     "editable": true
    },
@@ -476,7 +476,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d2e40c4d",
+   "id": "e91caeaf",
    "metadata": {
     "editable": true
    },
@@ -488,7 +488,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1e48456e",
+   "id": "5c78d187",
    "metadata": {
     "editable": true
    },
@@ -500,7 +500,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "38ced5b6",
+   "id": "ed3da21c",
    "metadata": {
     "editable": true
    },
@@ -510,7 +510,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1163c07b",
+   "id": "3e1b1c5b",
    "metadata": {
     "editable": true
    },
@@ -522,7 +522,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "becc087f",
+   "id": "e78923b1",
    "metadata": {
     "editable": true
    },
@@ -532,7 +532,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5ca2b09d",
+   "id": "e1b17e7e",
    "metadata": {
     "editable": true
    },
@@ -551,7 +551,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6572c77d",
+   "id": "77ece18e",
    "metadata": {
     "editable": true
    },
@@ -572,7 +572,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2a3f65e5",
+   "id": "d327d5a7",
    "metadata": {
     "editable": true
    },
@@ -584,7 +584,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2d264f77",
+   "id": "7102a93d",
    "metadata": {
     "editable": true
    },
@@ -595,7 +595,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "06b8a13c",
+   "id": "27bfcb69",
    "metadata": {
     "editable": true
    },
@@ -608,7 +608,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6d958ed3",
+   "id": "6278ac53",
    "metadata": {
     "editable": true
    },
@@ -620,7 +620,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6330f3f2",
+   "id": "3897e162",
    "metadata": {
     "editable": true
    },
@@ -630,7 +630,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ed6a9f67",
+   "id": "6e3ff648",
    "metadata": {
     "editable": true
    },
@@ -642,7 +642,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "de42ab8a",
+   "id": "176c5f9e",
    "metadata": {
     "editable": true
    },
@@ -652,7 +652,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4f36b126",
+   "id": "c5af703d",
    "metadata": {
     "editable": true
    },
@@ -664,7 +664,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0a7eef00",
+   "id": "948dd53c",
    "metadata": {
     "editable": true
    },
@@ -674,7 +674,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "29940f94",
+   "id": "7ebb1faf",
    "metadata": {
     "editable": true
    },
@@ -688,7 +688,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f2204679",
+   "id": "91c5fa5e",
    "metadata": {
     "editable": true
    },
@@ -700,7 +700,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d3f4597f",
+   "id": "e0a0244b",
    "metadata": {
     "editable": true
    },
@@ -710,7 +710,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c9e9ca01",
+   "id": "7db46562",
    "metadata": {
     "editable": true
    },
@@ -722,7 +722,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1c3062b6",
+   "id": "dfd3b2a2",
    "metadata": {
     "editable": true
    },
@@ -732,7 +732,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b455f707",
+   "id": "0a8c059c",
    "metadata": {
     "editable": true
    },
@@ -744,7 +744,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5ac8fdd3",
+   "id": "197c21a0",
    "metadata": {
     "editable": true
    },
@@ -754,7 +754,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "827927db",
+   "id": "f99f268e",
    "metadata": {
     "editable": true
    },
@@ -766,7 +766,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0c740a13",
+   "id": "6a8b2738",
    "metadata": {
     "editable": true
    },
@@ -776,7 +776,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a855fc3c",
+   "id": "3451f8f0",
    "metadata": {
     "editable": true
    },
@@ -792,7 +792,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "9dda8b9e",
+   "id": "2cceee67",
    "metadata": {
     "editable": true
    },
@@ -804,7 +804,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d160205c",
+   "id": "35f4e8bb",
    "metadata": {
     "editable": true
    },
@@ -814,7 +814,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1b7501a6",
+   "id": "21b8abf8",
    "metadata": {
     "editable": true
    },
@@ -826,7 +826,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d75a8c65",
+   "id": "67804133",
    "metadata": {
     "editable": true
    },
@@ -839,7 +839,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c9f718df",
+   "id": "475b65d6",
    "metadata": {
     "editable": true
    },
@@ -851,7 +851,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b07b6425",
+   "id": "7e68e582",
    "metadata": {
     "editable": true
    },
@@ -861,7 +861,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "215a8730",
+   "id": "7798cead",
    "metadata": {
     "editable": true
    },
@@ -873,7 +873,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7013d0f0",
+   "id": "06b5fc3f",
    "metadata": {
     "editable": true
    },
@@ -883,7 +883,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "d56b4ce0",
+   "id": "997f8e5d",
    "metadata": {
     "editable": true
    },
@@ -895,7 +895,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f9c6b14d",
+   "id": "9fec2088",
    "metadata": {
     "editable": true
    },
@@ -907,7 +907,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0bde16cb",
+   "id": "af56a994",
    "metadata": {
     "editable": true
    },
@@ -917,7 +917,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0a2869fc",
+   "id": "d50d4218",
    "metadata": {
     "editable": true
    },
@@ -929,7 +929,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "75b83b9b",
+   "id": "edbfbb74",
    "metadata": {
     "editable": true
    },
@@ -941,19 +941,19 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1e76d916",
+   "id": "684bbebb",
    "metadata": {
     "editable": true
    },
    "source": [
     "$$\n",
-    "C(\\boldsymbol{\\beta}=\\frac{\\vert\\vert (\\boldsymbol{y}-\\boldsymbol{X}\\boldsymbol{\\beta})\\vert\\vert_2^2}{2\\sigma^2}+\\frac{1}{\\tau}\\vert\\vert\\boldsymbol{\\beta}\\vert\\vert_1,\n",
+    "C(\\boldsymbol{\\beta})=\\frac{\\vert\\vert (\\boldsymbol{y}-\\boldsymbol{X}\\boldsymbol{\\beta})\\vert\\vert_2^2}{2\\sigma^2}+\\frac{1}{\\tau}\\vert\\vert\\boldsymbol{\\beta}\\vert\\vert_1,\n",
     "$$"
    ]
   },
   {
    "cell_type": "markdown",
-   "id": "09dfe26d",
+   "id": "42ad509f",
    "metadata": {
     "editable": true
    },
@@ -963,19 +963,19 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4037962f",
+   "id": "75efa6c7",
    "metadata": {
     "editable": true
    },
    "source": [
     "$$\n",
-    "C(\\boldsymbol{\\beta}=\\frac{\\vert\\vert (\\boldsymbol{y}-\\boldsymbol{X}\\boldsymbol{\\beta})\\vert\\vert_2^2}{2\\sigma^2}+\\lambda\\vert\\vert\\boldsymbol{\\beta}\\vert\\vert_1,\n",
+    "C(\\boldsymbol{\\beta})=\\frac{\\vert\\vert (\\boldsymbol{y}-\\boldsymbol{X}\\boldsymbol{\\beta})\\vert\\vert_2^2}{2\\sigma^2}+\\lambda\\vert\\vert\\boldsymbol{\\beta}\\vert\\vert_1,\n",
     "$$"
    ]
   },
   {
    "cell_type": "markdown",
-   "id": "39a85ba0",
+   "id": "b88067e5",
    "metadata": {
     "editable": true
    },
@@ -985,7 +985,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b263a1fe",
+   "id": "2223ad59",
    "metadata": {
     "editable": true
    },
@@ -1004,7 +1004,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "41730165",
+   "id": "adf4f844",
    "metadata": {
     "editable": true
    },
@@ -1032,7 +1032,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4076cee3",
+   "id": "eeacc972",
    "metadata": {
     "editable": true
    },
@@ -1058,7 +1058,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "11139cb3",
+   "id": "b162fc53",
    "metadata": {
     "editable": true
    },
@@ -1075,7 +1075,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b2bead9b",
+   "id": "d70c98f7",
    "metadata": {
     "editable": true
    },
@@ -1095,7 +1095,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "8df8364e",
+   "id": "220b6410",
    "metadata": {
     "editable": true
    },
@@ -1124,7 +1124,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6b5273f1",
+   "id": "68efa94d",
    "metadata": {
     "editable": true
    },
@@ -1149,7 +1149,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a260b371",
+   "id": "0c144baa",
    "metadata": {
     "editable": true
    },
@@ -1169,7 +1169,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2ff1e63c",
+   "id": "3dbef469",
    "metadata": {
     "editable": true
    },
@@ -1181,7 +1181,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "ab4b2e8c",
+   "id": "27061345",
    "metadata": {
     "editable": true
    },
@@ -1191,7 +1191,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "85b6fb62",
+   "id": "bc270a26",
    "metadata": {
     "editable": true
    },
@@ -1206,7 +1206,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "42449344",
+   "id": "4075e050",
    "metadata": {
     "editable": true
    },
@@ -1219,7 +1219,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "35e4f511",
+   "id": "19dd4b96",
    "metadata": {
     "editable": true
    },
@@ -1232,7 +1232,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c787234f",
+   "id": "f0fa1bc0",
    "metadata": {
     "editable": true
    },
@@ -1244,7 +1244,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "183711dc",
+   "id": "8ea697af",
    "metadata": {
     "editable": true
    },
@@ -1257,7 +1257,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2351078d",
+   "id": "6074b0df",
    "metadata": {
     "editable": true
    },
@@ -1268,7 +1268,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "408ba3b5",
+   "id": "17890a02",
    "metadata": {
     "editable": true
    },
@@ -1282,7 +1282,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3ea79849",
+   "id": "86770121",
    "metadata": {
     "editable": true
    },
@@ -1292,7 +1292,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "69439aad",
+   "id": "7447aaee",
    "metadata": {
     "editable": true
    },
@@ -1306,7 +1306,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e6c29fd8",
+   "id": "1a065454",
    "metadata": {
     "editable": true
    },
@@ -1319,7 +1319,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4bb52549",
+   "id": "299e45c4",
    "metadata": {
     "editable": true
    },
@@ -1332,7 +1332,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3430d548",
+   "id": "2e27eb1c",
    "metadata": {
     "editable": true
    },
@@ -1342,7 +1342,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "9ba636b3",
+   "id": "757e0395",
    "metadata": {
     "editable": true
    },
@@ -1355,7 +1355,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "cb19e98f",
+   "id": "821b4888",
    "metadata": {
     "editable": true
    },
@@ -1365,7 +1365,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3cc840d7",
+   "id": "1f66e8c1",
    "metadata": {
     "editable": true
    },
@@ -1378,7 +1378,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a5062213",
+   "id": "794b99f5",
    "metadata": {
     "editable": true
    },
@@ -1390,7 +1390,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "8d555244",
+   "id": "a7703593",
    "metadata": {
     "editable": true
    },
@@ -1409,7 +1409,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c4356604",
+   "id": "4d4c2830",
    "metadata": {
     "editable": true
    },
@@ -1422,7 +1422,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "09dc08a1",
+   "id": "08f438fa",
    "metadata": {
     "editable": true
    },
@@ -1434,7 +1434,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "dab5056a",
+   "id": "30554920",
    "metadata": {
     "editable": true
    },
@@ -1447,7 +1447,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "8a1f8583",
+   "id": "eb2d0659",
    "metadata": {
     "editable": true
    },
@@ -1467,7 +1467,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1be08ebb",
+   "id": "e3f406ba",
    "metadata": {
     "editable": true
    },
@@ -1490,7 +1490,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2a368353",
+   "id": "04ed2dd4",
    "metadata": {
     "editable": true
    },
@@ -1505,7 +1505,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6fee4a1a",
+   "id": "ca175052",
    "metadata": {
     "editable": true
    },
@@ -1517,7 +1517,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1a97c9ef",
+   "id": "cae9e5af",
    "metadata": {
     "editable": true
    },
@@ -1537,7 +1537,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "0a70afb2",
+   "id": "5d65b07a",
    "metadata": {
     "editable": true
    },
@@ -1557,7 +1557,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "dc32eaea",
+   "id": "b1bf73fb",
    "metadata": {
     "editable": true
    },
@@ -1581,7 +1581,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "016d0ab3",
+   "id": "1f98ac66",
    "metadata": {
     "editable": true
    },
@@ -1602,7 +1602,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3f371f0d",
+   "id": "cc88b1ee",
    "metadata": {
     "editable": true
    },
@@ -1632,7 +1632,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "abc56fe7",
+   "id": "8b721633",
    "metadata": {
     "editable": true
    },
@@ -1656,7 +1656,7 @@
   {
    "cell_type": "code",
    "execution_count": 1,
-   "id": "a3d2885b",
+   "id": "ad223832",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -1695,7 +1695,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5db67125",
+   "id": "17be41a1",
    "metadata": {
     "editable": true
    },
@@ -1705,7 +1705,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6f1b5417",
+   "id": "69421d74",
    "metadata": {
     "editable": true
    },
@@ -1716,7 +1716,7 @@
   {
    "cell_type": "code",
    "execution_count": 2,
-   "id": "9d98136a",
+   "id": "2729405e",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -1736,7 +1736,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c87eac4e",
+   "id": "236a42a1",
    "metadata": {
     "editable": true
    },
@@ -1754,7 +1754,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2f0f4313",
+   "id": "8fcdaadc",
    "metadata": {
     "editable": true
    },
@@ -1766,7 +1766,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7895ee8b",
+   "id": "7cc9cdf4",
    "metadata": {
     "editable": true
    },
@@ -1783,7 +1783,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "be454b28",
+   "id": "b7b6f4ad",
    "metadata": {
     "editable": true
    },
@@ -1795,7 +1795,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7475f8f9",
+   "id": "859ee059",
    "metadata": {
     "editable": true
    },
@@ -1805,7 +1805,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "fd472029",
+   "id": "459c3520",
    "metadata": {
     "editable": true
    },
@@ -1817,7 +1817,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b43c8f67",
+   "id": "07d724d8",
    "metadata": {
     "editable": true
    },
@@ -1834,7 +1834,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c47cfb6d",
+   "id": "ebe1aaa1",
    "metadata": {
     "editable": true
    },
@@ -1846,7 +1846,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "593188cd",
+   "id": "6827a56c",
    "metadata": {
     "editable": true
    },
@@ -1856,7 +1856,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "76de4d81",
+   "id": "1b5aabc1",
    "metadata": {
     "editable": true
    },
@@ -1868,7 +1868,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "afc38c97",
+   "id": "fd4da9e7",
    "metadata": {
     "editable": true
    },
@@ -1878,7 +1878,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "b0f2971c",
+   "id": "3ba15e20",
    "metadata": {
     "editable": true
    },
@@ -1890,7 +1890,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5a65e495",
+   "id": "3c912a7b",
    "metadata": {
     "editable": true
    },
@@ -1900,7 +1900,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "31419298",
+   "id": "43cb230f",
    "metadata": {
     "editable": true
    },
@@ -1916,7 +1916,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "217ddd53",
+   "id": "c723eb72",
    "metadata": {
     "editable": true
    },
@@ -1927,7 +1927,7 @@
   {
    "cell_type": "code",
    "execution_count": 3,
-   "id": "ece05002",
+   "id": "52d1b1bf",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -1992,7 +1992,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "de6dc4e2",
+   "id": "05905c84",
    "metadata": {
     "editable": true
    },
@@ -2003,7 +2003,7 @@
   {
    "cell_type": "code",
    "execution_count": 4,
-   "id": "da218205",
+   "id": "15883cc8",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2060,7 +2060,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "5ea5df06",
+   "id": "d01031bc",
    "metadata": {
     "editable": true
    },
@@ -2098,7 +2098,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "40f41d74",
+   "id": "3f1014f9",
    "metadata": {
     "editable": true
    },
@@ -2109,7 +2109,7 @@
   {
    "cell_type": "code",
    "execution_count": 5,
-   "id": "03bb50ae",
+   "id": "0f7f0a2b",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2191,7 +2191,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "cd11e9fd",
+   "id": "5c0a1e98",
    "metadata": {
     "editable": true
    },
@@ -2216,7 +2216,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6cf68ff2",
+   "id": "423a173e",
    "metadata": {
     "editable": true
    },
@@ -2244,7 +2244,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c445bfb2",
+   "id": "531cc595",
    "metadata": {
     "editable": true
    },
@@ -2257,7 +2257,7 @@
   {
    "cell_type": "code",
    "execution_count": 6,
-   "id": "8e26035a",
+   "id": "9f463ef6",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2357,7 +2357,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "86a6b012",
+   "id": "fb460894",
    "metadata": {
     "editable": true
    },
@@ -2368,7 +2368,7 @@
   {
    "cell_type": "code",
    "execution_count": 7,
-   "id": "4a0e1afd",
+   "id": "84f5480a",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2457,7 +2457,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "bb1e0f15",
+   "id": "2e9a67d4",
    "metadata": {
     "editable": true
    },
@@ -2467,7 +2467,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "83c87d33",
+   "id": "a487a944",
    "metadata": {
     "editable": true
    },
@@ -2480,7 +2480,7 @@
   {
    "cell_type": "code",
    "execution_count": 8,
-   "id": "74eaac59",
+   "id": "82c29352",
    "metadata": {
     "collapsed": false,
     "editable": true
@@ -2558,7 +2558,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "aa703354",
+   "id": "c76ccd85",
    "metadata": {
     "editable": true
    },
@@ -2568,7 +2568,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f8bffca6",
+   "id": "3131e8d4",
    "metadata": {
     "editable": true
    },
@@ -2597,7 +2597,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "109c07d6",
+   "id": "0b408cd2",
    "metadata": {
     "editable": true
    },
@@ -2613,7 +2613,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "1ea48f22",
+   "id": "e127a896",
    "metadata": {
     "editable": true
    },
@@ -2632,7 +2632,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "212f90ec",
+   "id": "d0096384",
    "metadata": {
     "editable": true
    },
@@ -2646,7 +2646,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a019e7cb",
+   "id": "c01cf074",
    "metadata": {
     "editable": true
    },
@@ -2658,7 +2658,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "2ca46c43",
+   "id": "0e482bf6",
    "metadata": {
     "editable": true
    },
@@ -2669,7 +2669,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "c61ed9c8",
+   "id": "5fdd00a2",
    "metadata": {
     "editable": true
    },
@@ -2681,7 +2681,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "96d84043",
+   "id": "5c65ebd6",
    "metadata": {
     "editable": true
    },
@@ -2693,7 +2693,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e53b66df",
+   "id": "fab9aceb",
    "metadata": {
     "editable": true
    },
@@ -2709,7 +2709,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "71d542a3",
+   "id": "b5c38a6a",
    "metadata": {
     "editable": true
    },
@@ -2720,7 +2720,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "01b18637",
+   "id": "fb7b60e4",
    "metadata": {
     "editable": true
    },
@@ -2743,7 +2743,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "e35bdcc1",
+   "id": "ab45dff9",
    "metadata": {
     "editable": true
    },
@@ -2754,7 +2754,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "15b7ea3c",
+   "id": "3714ed57",
    "metadata": {
     "editable": true
    },
@@ -2766,7 +2766,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "a4c5f625",
+   "id": "eb804be9",
    "metadata": {
     "editable": true
    },
@@ -2778,7 +2778,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "450007e4",
+   "id": "b8127b07",
    "metadata": {
     "editable": true
    },
@@ -2792,7 +2792,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "3bcf81c1",
+   "id": "8e5964fc",
    "metadata": {
     "editable": true
    },
@@ -2823,7 +2823,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f69a019e",
+   "id": "53b8a320",
    "metadata": {
     "editable": true
    },
@@ -2845,7 +2845,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "95b37da0",
+   "id": "42b13d5f",
    "metadata": {
     "editable": true
    },
@@ -2857,7 +2857,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "241c2335",
+   "id": "e273408f",
    "metadata": {
     "editable": true
    },
@@ -2870,7 +2870,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "cf794384",
+   "id": "1dc4ad8b",
    "metadata": {
     "editable": true
    },
@@ -2882,7 +2882,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "4cd5260a",
+   "id": "1a4b573f",
    "metadata": {
     "editable": true
    },
@@ -2894,7 +2894,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "7361e846",
+   "id": "59e15b92",
    "metadata": {
     "editable": true
    },
@@ -2906,7 +2906,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "6a07837b",
+   "id": "6b9440f8",
    "metadata": {
     "editable": true
    },
diff --git a/doc/src/week37/week37.do.txt b/doc/src/week37/week37.do.txt
index 39c2d5e8b..d9913ab56 100644
--- a/doc/src/week37/week37.do.txt
+++ b/doc/src/week37/week37.do.txt
@@ -411,14 +411,14 @@ constants terms that do not depend on $\beta$, we have
 
 !bt
 \[
-C(\bm{\beta}=\frac{\vert\vert (\bm{y}-\bm{X}\bm{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\bm{\beta}\vert\vert_1,
+C(\bm{\beta})=\frac{\vert\vert (\bm{y}-\bm{X}\bm{\beta})\vert\vert_2^2}{2\sigma^2}+\frac{1}{\tau}\vert\vert\bm{\beta}\vert\vert_1,
 \]
 !et
 and replacing $1/\tau$ with $\lambda$ we have
 
 !bt
 \[
-C(\bm{\beta}=\frac{\vert\vert (\bm{y}-\bm{X}\bm{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\bm{\beta}\vert\vert_1,
+C(\bm{\beta})=\frac{\vert\vert (\bm{y}-\bm{X}\bm{\beta})\vert\vert_2^2}{2\sigma^2}+\lambda\vert\vert\bm{\beta}\vert\vert_1,
 \]
 !et
 which is our Lasso cost function!