SOURCE

new Vue({
    el: "#app",
    data: {
        name: 'abyss',
        counter: 0,
        secondCounter: 0
    },
    computed: {
        output: function() {
            console.log('Computed');
            return this.counter > 5 ? "Greater 5" : "Smaller 5"; 
        }
    },
    watch: {
        counter: function(value) {
            var vm = this;
            setTimeout(function() {
                vm.secondCounter++;
            }, 2000)
        }
    },
    methods: {
        result: function() {
            console.log('method');
            return this.counter > 5 ? "Greater 5" : "Smaller 5";
        }
    }
});

<div id="app">
    <button v-on:click="counter++">Increase</button>
    <button v-on:click="counter--">Decrease</button>
    <button v-on:click="secondCounter++">Increase Second</button>
    <p>Counter: {{ counter }} | {{ secondCounter }}</p>
    <p>Result: {{ result() }} | {{ output }}</p>
</div>