Almost spot on

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Rate a review "exceptional" if it gives readers outstanding advice for making a good buying decision

The review covers all aspects of the product and its user-friendliness which would be relevant to making a product choice. All remarks are founded on evidence from personal experience and the author remains objective throughout. A reader could find sufficient information here to base his/her purchase decision on this review alone. Please attend, that you can evaluate only 5 times "exceptional" at the time of 24 hours.

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Rate a review "less helpful" if it gives somewhat inaccurate and/or poorly presented information.

The review is not always objective or founded on evidence from the author's experience. The presentation and structure are unclear.

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Rate a review "very helpful" if it clearly supports others in making a good buying decision

The review covers a wide range of product features and the author's position is clearly-explained, well-structured and founded, for the most part, on solid evidence. This review would be of great use to somebody making a product choice, but would have to be used in conjunction with other information sources.

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Rate a review "not helpful" if it gives inaccurate, offensive and useless information.

The review is not a helpful decision-making aid. The information it provides is subjective and lacks foundation. Perhaps the content contains comments which do not relate to the product and may be offensive to other members.

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Rate a review "helpful" if it supports readers in making a good buying decision.

The review is accurate and clear. The author may not provide complete information but what (s)he does say is useful. The review would give readers an idea of the quality of the product.

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Rate a review "off topic" if it has been posted in the wrong place and/or does not discuss the product.

Reviews relating to products in other categories, or those which stray onto unrelated subjects should be rated "off topic". This will let other readers know that they need not read the review when seeking information that would be useful in a purchase decision.