diff --git a/64-dimred.Rmd b/64-dimred.Rmd
index 556f4d2..5c50e8f 100644
--- a/64-dimred.Rmd
+++ b/64-dimred.Rmd
@@ -23,7 +23,7 @@ existing domain knowledge) the results of any clustering algorithm.
   variables. A typical example in omics is to summarise (and
   visualise) the relation between samples along two dimensions (which
   can easily be plotted) even if the data consists of tens of
-  thousands of dimensions ( genes). Dimensionality reduction is often
+  thousands of dimensions (genes). Dimensionality reduction is often
   used to facilitate visualisation of the data, as well as a
   pre-processing method before supervised learning.
 
diff --git a/docs/404.html b/docs/404.html
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
-<meta name="date" content="2024-11-17" />
+<meta name="date" content="2024-11-18" />
 
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diff --git a/docs/index.html b/docs/index.html
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
-<meta name="date" content="2024-11-17" />
+<meta name="date" content="2024-11-18" />
 
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@@ -349,7 +349,7 @@ <h2>Setup<div class="tooltip"><button class="internal-link-btn" onclick="copy_li
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diff --git a/docs/sec-biostrings.html b/docs/sec-biostrings.html
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
-<meta name="date" content="2024-11-17" />
+<meta name="date" content="2024-11-18" />
 
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@@ -487,7 +487,7 @@ <h2>
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
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@@ -511,7 +511,7 @@ <h3>Exercise 3<div class="tooltip"><button class="internal-link-btn" onclick="co
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diff --git a/docs/sec-dimred.html b/docs/sec-dimred.html
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
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+<meta name="date" content="2024-11-18" />
 
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@@ -233,7 +233,7 @@ <h1>
 variables. A typical example in omics is to summarise (and
 visualise) the relation between samples along two dimensions (which
 can easily be plotted) even if the data consists of tens of
-thousands of dimensions ( genes). Dimensionality reduction is often
+thousands of dimensions (genes). Dimensionality reduction is often
 used to facilitate visualisation of the data, as well as a
 pre-processing method before supervised learning.</li>
 </ul>
@@ -1340,7 +1340,7 @@ <h2>
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 </p>
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+2024-11-18
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 </p>
diff --git a/docs/sec-mlintro.html b/docs/sec-mlintro.html
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@@ -13,7 +13,7 @@
 
 <meta name="author" content="Laurent Gatto" />
 
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diff --git a/docs/sec-norm.html b/docs/sec-norm.html
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@@ -13,7 +13,7 @@
 
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diff --git a/docs/sec-obj.html b/docs/sec-obj.html
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--- a/docs/sec-obj.html
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@@ -13,7 +13,7 @@
 
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@@ -1029,7 +1029,7 @@ <h2>
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diff --git a/docs/sec-refresher.html b/docs/sec-refresher.html
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@@ -13,7 +13,7 @@
 
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diff --git a/docs/sec-si.html b/docs/sec-si.html
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@@ -13,7 +13,7 @@
 
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diff --git a/docs/sec-sl.html b/docs/sec-sl.html
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+2024-11-18
  using 
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diff --git a/docs/sec-testing.html b/docs/sec-testing.html
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@@ -1134,7 +1134,7 @@ <h3>The coin example, step by step<div class="tooltip"><button class="internal-l
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diff --git a/docs/sec-ul.html b/docs/sec-ul.html
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diff --git a/docs/sec-vis.html b/docs/sec-vis.html
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@@ -949,7 +949,7 @@ <h2>
 <span id="cb36-9"><a href="sec-vis.html#cb36-9" tabindex="-1"></a>p2 <span class="ot">&lt;-</span>  <span class="fu">ggplot</span>(sim, <span class="fu">aes</span>(<span class="fu">log</span>(x))) <span class="sc">+</span></span>
 <span id="cb36-10"><a href="sec-vis.html#cb36-10" tabindex="-1"></a>    <span class="fu">geom_histogram</span>(<span class="at">bins =</span> <span class="dv">30</span>)</span>
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-<pre><code>## Warning: Removed 7898 rows containing non-finite outside the scale range
+<pre><code>## Warning: Removed 7988 rows containing non-finite outside the scale range
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