<html>
    <head>
        <script>
            function test() {
                if (document.getElementById("rb").checked)
                    document.getElementById("result").innerHTML = "Test Passed.  Radio button is checked by default";
            }
        </script>
    </head>
<body onload="test()">
This tests that radio buttons are checked by default, even when the name attribute is parsed after the checked attribute.
<br><br>
<input type="radio" checked name="test_group" id="rb">This radio button should be checked by default
<br><br>
<div id="result">Test Failed.  Radio button is not checked by default.</div>
</body>
</html>