diff --git a/pointprocesses/lecture/pointprocessscetchA.eps b/pointprocesses/lecture/pointprocessscetchA.eps
index bdf6699..910c42e 100644
--- a/pointprocesses/lecture/pointprocessscetchA.eps
+++ b/pointprocesses/lecture/pointprocessscetchA.eps
@@ -1,7 +1,7 @@
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 %%Title: pointprocessscetchA.tex
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+%%CreationDate: Mon Dec 21 20:05:25 2020
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diff --git a/pointprocesses/lecture/pointprocessscetchA.pdf b/pointprocesses/lecture/pointprocessscetchA.pdf
index 8d6a7dd..05bcdac 100644
--- a/pointprocesses/lecture/pointprocessscetchA.pdf
+++ b/pointprocesses/lecture/pointprocessscetchA.pdf
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diff --git a/pointprocesses/lecture/pointprocessscetchB.eps b/pointprocesses/lecture/pointprocessscetchB.eps
index f58e266..10279c1 100644
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+++ b/pointprocesses/lecture/pointprocessscetchB.eps
@@ -1,7 +1,7 @@
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+  /CreationDate (Mon Dec 21 20:05:26 2020)
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diff --git a/pointprocesses/lecture/pointprocessscetchB.pdf b/pointprocesses/lecture/pointprocessscetchB.pdf
index 87d8a5e..c466f9a 100644
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diff --git a/regression/code/gradientDescent.m b/regression/code/gradientDescent.m
index 3fb9643..f0f7ef1 100644
--- a/regression/code/gradientDescent.m
+++ b/regression/code/gradientDescent.m
@@ -34,7 +34,7 @@ function gradmse = meanSquaredGradient(x, y, func, p)
   ph = eye(length(p))*h;  % ... for each parameter
   mse = meanSquaredError(x, y, func, p);
   for i = 1:length(p)     % for each coordinate ...
-    msepi = meanSquaredError(x, y, func, p + ph(:,i));
+    msepi = meanSquaredError(x, y, func, p(:) + ph(:,i));
     gradmse(i) = (msepi - mse)/h;
   end
 end
diff --git a/regression/exercises/exp2plot.pdf b/regression/exercises/exp2plot.pdf
index 7d97518..f42670b 100644
Binary files a/regression/exercises/exp2plot.pdf and b/regression/exercises/exp2plot.pdf differ
diff --git a/regression/exercises/gradientdescent.m b/regression/exercises/gradientdescent.m
index aaeacfe..b7d61a5 100644
--- a/regression/exercises/gradientdescent.m
+++ b/regression/exercises/gradientdescent.m
@@ -29,7 +29,7 @@ end
 
 function gradmse = msegradient(t, x, func, p)
   gradmse = zeros(size(p));
-  h = 1e-3;   % stepsize for derivative
+  h = 1e-7;   % stepsize for derivative
   ph = eye(length(p))*h;  % ... for each parameter
   mse = meansquarederror(t, x, func, p);
   for i = 1:length(p)     % for each coordinate ...