diff --git a/05-challenge.html b/05-challenge.html
index 8f1a824..f62e970 100644
--- a/05-challenge.html
+++ b/05-challenge.html
@@ -548,8 +548,8 @@ <h3 class="code-label">PYTHON<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="sourceCode python" tabindex="0"><code class="sourceCode python"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a>pu <span class="op">=</span> signal[<span class="st">'pileup'</span>]</span>
 <span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a></span>
 <span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a>pu_sf <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"nominal"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systup"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systdown"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"up"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
+<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"down"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
 </div>
 </div>
 <div class="section level3">
diff --git a/aio.html b/aio.html
index 659c4db..e2b4c7f 100644
--- a/aio.html
+++ b/aio.html
@@ -1383,8 +1383,8 @@ <h3 class="code-label">PYTHON<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="sourceCode python" tabindex="0"><code class="sourceCode python"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a>pu <span class="op">=</span> signal[<span class="st">'pileup'</span>]</span>
 <span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a></span>
 <span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a>pu_sf <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"nominal"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systup"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systdown"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"up"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
+<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"down"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
 </div>
 </div>
 <div class="section level3">
diff --git a/instructor/05-challenge.html b/instructor/05-challenge.html
index ba26aa1..ef8283a 100644
--- a/instructor/05-challenge.html
+++ b/instructor/05-challenge.html
@@ -549,8 +549,8 @@ <h3 class="code-label">PYTHON<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="sourceCode python" tabindex="0"><code class="sourceCode python"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a>pu <span class="op">=</span> signal[<span class="st">'pileup'</span>]</span>
 <span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a></span>
 <span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a>pu_sf <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"nominal"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systup"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systdown"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"up"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
+<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"down"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
 </div>
 </div>
 <div class="section level3">
diff --git a/instructor/aio.html b/instructor/aio.html
index c0de0b0..38d11be 100644
--- a/instructor/aio.html
+++ b/instructor/aio.html
@@ -1387,8 +1387,8 @@ <h3 class="code-label">PYTHON<i aria-hidden="true" data-feather="chevron-left"><
 <pre class="sourceCode python" tabindex="0"><code class="sourceCode python"><span id="cb11-1"><a href="#cb11-1" tabindex="-1"></a>pu <span class="op">=</span> signal[<span class="st">'pileup'</span>]</span>
 <span id="cb11-2"><a href="#cb11-2" tabindex="-1"></a></span>
 <span id="cb11-3"><a href="#cb11-3" tabindex="-1"></a>pu_sf <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"nominal"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systup"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
-<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"systdown"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
+<span id="cb11-4"><a href="#cb11-4" tabindex="-1"></a>pu_sfup <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"up"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span>
+<span id="cb11-5"><a href="#cb11-5" tabindex="-1"></a>pu_sfdn <span class="op">=</span> [pileupcorr.evaluate(nInts,<span class="st">"down"</span>) <span class="cf">for</span> nInts <span class="kw">in</span> pu]</span></code></pre>
 </div>
 </div>
 <div class="section level3">
diff --git a/md5sum.txt b/md5sum.txt
index cb61a79..1f9454b 100644
--- a/md5sum.txt
+++ b/md5sum.txt
@@ -7,7 +7,7 @@
 "episodes/introduction.md" "f4722b811504e69899f6b660dc7d4048" "site/built/introduction.md" "2024-07-24"
 "episodes/02-sources.md" "ec19118794ca18c30f90b8dff360cb5e" "site/built/02-sources.md" "2024-07-31"
 "episodes/03-corrections.md" "ad718565299b71892d9bac623ce7eec5" "site/built/03-corrections.md" "2024-07-26"
-"episodes/05-challenge.md" "5a8c2d6f02d2b1888ead5e5c76f20d6f" "site/built/05-challenge.md" "2024-07-31"
+"episodes/05-challenge.md" "d9efc7412f2fd0f32723aceb2c54edbc" "site/built/05-challenge.md" "2024-07-31"
 "instructors/instructor-notes.md" "cae72b6712578d74a49fea7513099f8c" "site/built/instructor-notes.md" "2024-07-22"
 "learners/setup.md" "6620d9af0c55cca6c86be14d788d90bb" "site/built/setup.md" "2024-07-23"
 "profiles/learner-profiles.md" "60b93493cf1da06dfd63255d73854461" "site/built/learner-profiles.md" "2024-07-22"
diff --git a/pkgdown.yml b/pkgdown.yml
index 3d40352..584ff14 100644
--- a/pkgdown.yml
+++ b/pkgdown.yml
@@ -2,4 +2,4 @@ pandoc: 3.1.11
 pkgdown: 2.1.0
 pkgdown_sha: ~
 articles: {}
-last_built: 2024-07-31T13:43Z
+last_built: 2024-07-31T15:36Z