diff --git a/lectures/_config.yml b/lectures/_config.yml
index aa9c7a1..5760ff3 100644
--- a/lectures/_config.yml
+++ b/lectures/_config.yml
@@ -81,7 +81,7 @@ sphinx:
       twitter: quantecon
       twitter_logo_url: https://assets.quantecon.org/img/qe-twitter-logo.png
       og_logo_url: https://assets.quantecon.org/img/qe-og-logo.png
-      description: This website presents a set of lectures on dynamic linear economies and tools needed for this this class of economic models.
+      description: This website presents a set of lectures on dynamic linear economies and tools needed for this class of economic models.
       keywords: Python, QuantEcon, Quantitative Economics, Economics, Sloan, Alfred P. Sloan Foundation, Tom J. Sargent, John Stachurski
       analytics:
         google_analytics_id: G-D5TQMHKC2V