function redirect(url) {
  redirectToURL(url.value);
}

function redirectToURL(url) {
  window.location = url;
}

function filterSet(baseURL, id) {
  var value = $("#attr" + id).val();
  if (value == -1) {
    if (baseURL.substr(-2) == "&a") {
      baseURL = baseURL.substr(0, baseURL.length - 2);
    }
    redirectToURL(baseURL);
  } else if (value == "") {
    return;
  } else {
    redirectToURL(baseURL + id + "=" + value);
  }
}