Deselect checkbox in angularJS

I am using the following code:

<input type="checkbox" value="{{F}}" ng-model="IsChecked" ng-change="ModifyFilter(IsChecked,$index)">{{F}}

with the Controller:

$scope.ModifyFilter = function (IsChecked, index) {
  if (IsChecked) {        
    $scope.ActiveFilters.push($scope.Filters[index]);   
  } else {
    var indexz = $scope.ActiveFilters.indexOf($scope.Filters[index]);
    $scope.ActiveFilters.splice(indexz, 1);
  }
  $scope.ApplyFilter();
};

This works fine, however I am unable to deselect my checkboxes. This is in the browser and iOS when built with ionic.