How to get value of chcecked checkbox - angularJS

J started learn Angular and I have trouble with getting value of checkboxes.

<label ng-repeat="role in groupsapp">
<input type="checkbox" ng-click="selectedRole([role.name,role.id,????])"></label>

How get value checked/unchecked in place "???" I found also:

ng-true-value="__true"
ng-false-value="__false"

but I don't know how to get this value of checkbox, anyone can help ?