Issue with (this).val and select box (combo)

Issue with (this).val and select box (combo)

I've been over my head this last few days triying to create a combo select (the option "chile" makes the next select display).

Im using this script to handle the request.
  1. $(document).ready(function(){$("#selectionpais").change(function(){
  2. if ($(this).attr("value") != "chile"){$("#ciudad").hide();}
  3. else {$("#ciudad").show()} ;
  4. });           
  5. });
And this is the select option;

  1. <select name="pais" id="selectionpais">
  2. <option value="..." selected="selected">....</option>
  3. <option value="chile" >Chile</option>
  4. <option value="af">Afganistán</option>
  5. </select>
And this is the select that should be shown after the user has selected the option chile.

  1. <select id="ciudad" name="ciudad" class="ciudad">
  2. <option>Santiago</option>
  3. </select>
The page is hosted here (if you find any errors or plain stupidity in the making please let me know);
htto://meds.chorrillana.cl/Index.html

Any help would be deeply appreciated 'cause I just cant seem to get it working.