diff --git a/travis_tests.py b/travis_tests.py
index 239d99e2..1e420c8e 100644
--- a/travis_tests.py
+++ b/travis_tests.py
@@ -33,7 +33,7 @@
 
 import matplotlib 
 matplotlib.use('pdf')
-matplotlib.rcParams['figure.size'] = (4,3)
+matplotlib.rcParams[u'figure.figsize'] = (4,3)
 
 import nose 
 nose.main('GPy', defaultTest='GPy/testing/plotting_tests.py')