diff --git a/examples/cluster/cluster-radial.js b/examples/cluster/cluster-radial.js
index f29da687..c7c505cf 100644
--- a/examples/cluster/cluster-radial.js
+++ b/examples/cluster/cluster-radial.js
@@ -1,16 +1,16 @@
-var r = 960 / 2;
+var radius = 960 / 2;
 
 var cluster = d3.layout.cluster()
-    .size([360, r - 120]);
+    .size([360, radius - 120]);
 
 var diagonal = d3.svg.diagonal.radial()
     .projection(function(d) { return [d.y, d.x / 180 * Math.PI]; });
 
 var vis = d3.select("#chart").append("svg")
-    .attr("width", r * 2)
-    .attr("height", r * 2)
+    .attr("width", radius * 2)
+    .attr("height", radius * 2)
   .append("g")
-    .attr("transform", "translate(" + r + "," + r + ")");
+    .attr("transform", "translate(" + radius + "," + radius + ")");
 
 d3.json("../data/flare.json", function(json) {
   var nodes = cluster.nodes(json);
diff --git a/examples/cluster/cluster.js b/examples/cluster/cluster.js
index f537befb..289659e2 100644
--- a/examples/cluster/cluster.js
+++ b/examples/cluster/cluster.js
@@ -1,15 +1,15 @@
-var w = 960,
-    h = 2200;
+var width = 960,
+    height = 2200;
 
 var cluster = d3.layout.cluster()
-    .size([h, w - 160]);
+    .size([height, width - 160]);
 
 var diagonal = d3.svg.diagonal()
     .projection(function(d) { return [d.y, d.x]; });
 
 var vis = d3.select("#chart").append("svg")
-    .attr("width", w)
-    .attr("height", h)
+    .attr("width", width)
+    .attr("height", height)
   .append("g")
     .attr("transform", "translate(40, 0)");