How to automatically set checkbox to true when dropdownlist on change?

I have multiple group which each of them consist of a checkbox and a dropdownlist which group together, when the dropdown list for the particular group is changed then the checkbox also will automatically set to checked.

<div class="form-group">
        <div class="input-group col-md-12">
          <span class="input-group-addon">
            <input type="checkbox" name="filter[]" value="1">
          </span>
            <select class="dateselectpicker form-control"id="filter"title="Filter">
                <option>a</option>
                <option>b</option>
            </select>
        </div>
    </div>  

<div class="form-group">
            <div class="input-group col-md-12">
              <span class="input-group-addon">
                <input type="checkbox" name="filter[]" value="2">
              </span>
                <select class="dateselectpicker form-control"id="filter1"title="Filter">
                    <option>a</option>
                    <option>b</option>
                </select>
            </div>
        </div>  

For example, when i select the first filter, then the checkbox for first filter will set to checked. Only when dropdown list on change. How can i do this?