Java script confirm with yes or no

Question

Hi,

 function AssignValueOnCheckboxTick(RouteId, StopNo, totemps, tripid, triptype)
{
       if (document.getElementById(RouteId).checked == true)
{
           if (triptype == 'P' && StopNo == 1)
{
              if ( window.confirm("Do you want to display second employee locality?"))
                {

                  }
         else
             {
             }

}

}
}
my problem is  i want to display yes or no instead of ok cancel .please suggest solution.

Regards,
Balu reddy