diff --git a/auctionsim/generators.go b/auctionsim/generators.go
index 91edc0a..a67076a 100644
--- a/auctionsim/generators.go
+++ b/auctionsim/generators.go
@@ -1,7 +1,7 @@
 package auctionsim
 
 import (
-	"math"
+	"math/rand"
 )
 
 /**
@@ -63,11 +63,11 @@ func (b *BiddersFromDistributions) Generate() (Bidder, bool) {
 /**
  * NormalDistribution is a Distribution representing the normal distribution
  * with some specified standard deviation and mean. Multiple instances of
- * this type can share a math.Rand as long as they are not queried concurrently
- * (since math.Rand is not threadsafe).
+ * this type can share a rand.Rand as long as they are not queried concurrently
+ * (since rand.Rand is not threadsafe).
  */
 type NormalDistribution struct {
-	Rand *math.Rand
+	Rand *rand.Rand
 	StdDev float64
 	Mean float64
 }