Google started enabling a vote sytem based on 1-5 rates for Videos on Youtube. They noticed people were using it as a mere boolean switch: 1 or 5.

You may use a Star system, but expect rather unbalanced results where most of the feedback will come in the shape of 1(noup) - 5(liike). You may want to skip the experiment and rather design a simple 'yay/nay' approach.

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