diff --git a/matlab/McMCDiagnostics.m b/matlab/McMCDiagnostics.m
index 83945ac132518147bbb553920d3051375317ecc2..ed719034cf5b59be6e972e0c883e5e9c69ceeebc 100644
--- a/matlab/McMCDiagnostics.m
+++ b/matlab/McMCDiagnostics.m
@@ -81,7 +81,7 @@ end
 
 if nblck == 1 % Brooks and Gelman tests need more than one block
     convergence_diagnostics_geweke=zeros(npar,4+2*length(options_.convergence.geweke.taper_steps));
-    if any(options_.convergence.geweke.geweke_interval<0) || any(options_.convergence.geweke.geweke_interval>1) || length(any(options_.convergence.geweke.geweke_interval<0))~=2 ...
+    if any(options_.convergence.geweke.geweke_interval<0) || any(options_.convergence.geweke.geweke_interval>1) || length(options_.convergence.geweke.geweke_interval)~=2 ...
         || (options_.convergence.geweke.geweke_interval(2)-options_.convergence.geweke.geweke_interval(1)<0)
         fprintf('\nCONVERGENCE DIAGNOSTICS: Invalid option for geweke_interval. Using the default of [0.2 0.5].\n')
         options_.convergence.geweke.geweke_interval=[0.2 0.5];