diff --git a/content/GA_2_5/old_Analysis_GA_solution.ipynb b/content/GA_2_5/old_Analysis_GA_solution.ipynb
index 7ac31c77edd207c4b96fd7b5877a399ee87fba07..f7a5aac310c51bf67c68ac03f14fa410a7b998a3 100644
--- a/content/GA_2_5/old_Analysis_GA_solution.ipynb
+++ b/content/GA_2_5/old_Analysis_GA_solution.ipynb
@@ -455,7 +455,6 @@
    "source": [
     "# define parameters, case study (network) list and the directory where their files are\n",
     "extension_factor = 1.5  # capacity after extension (1.5 means add 50%)\n",
-    "beta = 2  # parameter to use in link travel time function (explained later)\n",
     "\n",
     "networks = ['SiouxFalls']\n",
     "networks_dir = os.getcwd() +'/input/TransportationNetworks'\n",