diff --git a/tests/particle/benchmark.m b/tests/particle/benchmark.m
index 6531fa3bc..99a99cb64 100644
--- a/tests/particle/benchmark.m
+++ b/tests/particle/benchmark.m
@@ -155,4 +155,4 @@ y = series(:,1) + 0.00158*randn(size(series(:,1)));
 l = series(:,2) + 0.0011*randn(size(series(:,2)));
 i = series(:,3) + 0.000866*randn(size(series(:,3)));
 
-ti = [1950:0.25:1997.75] ;
\ No newline at end of file
+clear series;
\ No newline at end of file
diff --git a/tests/particle/extreme.m b/tests/particle/extreme.m
index c6a7dba26..bb0919457 100644
--- a/tests/particle/extreme.m
+++ b/tests/particle/extreme.m
@@ -155,4 +155,4 @@ y = series(:,1) + 0.00158*randn(size(series(:,1)));
 l = series(:,2) + 0.0011*randn(size(series(:,2)));
 i = series(:,3) + 0.000866*randn(size(series(:,3)));
 
-ti = [1950:0.25:1997.75] ;
\ No newline at end of file
+clear series;
\ No newline at end of file
diff --git a/tests/particle/risky.m b/tests/particle/risky.m
index 4d0b7a829..0eb2f0206 100644
--- a/tests/particle/risky.m
+++ b/tests/particle/risky.m
@@ -155,4 +155,4 @@ y = series(:,1) + 0.0175*randn(size(series(:,1)));
 l = series(:,2) + 0.00312*randn(size(series(:,2)));
 i = series(:,3) + 0.00465*randn(size(series(:,3)));
 
-ti = [1950:0.25:1997.75] ;
\ No newline at end of file
+clear series;
\ No newline at end of file