Problems adding Javascript embed

I am trying to add this code in a post of mine
<script type="text/javascript" >document.write('<script src="http' + ( (new String(document.location)).indexOf("s") > 0 ? "s" : "") + '://www.surveygizmo.com/s3/js/283999/f7095e536a51?__ref=' + escape(document.location) + '" type="text/javascript" ></scr' + 'ipt>');</script><noscript>This survey is powered by SurveyGizmo's <a href="http://www.surveygizmo.com">online survey software</a>. <a href="http://www.surveygizmo.com/s3/jsfallback/283999/f7095e536a51">Please take my survey now</a></noscript>

However when i do add this, the page is blank.
Anyone know how i can fix this?