JavaScript，retreive值进入复选框

Question

我的for循环很好，我得到了transportationOutput和trasportation2的值，我想检查两个值是否相等，选中右侧复选框输入，但是如果条件没有进入我不知道为什么，我尝试将==替换为===，但也不起作用

trasportation = "car-train" //value from database
var trasportation2 = document.getElementsByName("transportation");
var transportationOutput = trasportation.split("-");


for (var i = 0; i < transportationOutput.length; i++) {
  for (var j = 0; j < trasportation2.length; j++) {
    if (trasportation2[j].value == transportationOutput[i]) {
      trasportation2[j].checked = true;
    }
  }
}

<label>transportation</label>

<input type="checkbox" id="localTransportID" name="transportation" value="car"> car
<input type="checkbox" id="localTransportID" name="transportation" value="bus"> bus
<input type="checkbox" id="localTransportID" name="transportation" value="train"> train
<input type="checkbox" id="localTransportID" name="transportation" value="airplane"> airplane