The lies behind online ratings and reviews
Ratings and reviews lie. Simple, subtle lies, but lies all the same. And I suspect most people will never know.
This is Part2 in a series about Ratings and Reviews. To read Part1 click on: Introduction to Ratings and Reviews
“Professional” reviews
The first time I realized what a con ratings could be was when I visited Dubai. I was travelling with a group of friends and one of them booked the hotels. It was quite a surprise to hear we’d booked into a 5-star hotel for what seemed like a 3-star price. It transpired that this was not because my friend had negotiated a great deal, but because hotel stars in Dubai are dispersed as liberally as banking bonuses. Dubai is the land of the 7-star hotel and I’m afraid that has nothing to do with the Burj Al Arab being better than the 5-star Carlyle in New York or Cipriani in Venice.
Thankfully, one of the great things about online consumer-generated Ratings and Reviews is their potential to overwhelm organisational bias assuming a large number of “real people” comment. However even apparently unbiased people give biased reviews. Alongside a trick of averages, these biases help cloud the validity of ratings and reviews.
So how do online ratings and reviews lie?
There are four key ways in which ratings and reviews lie. There may be more but these are the ones that jump out at me.
1. There is no “zero” score.
Ask most people “When is a product good or bad?” and they’ll say above 2.5 is good and below 2.5 is bad. The assumption is that 2.5 is the mean average score that can be awarded. However that’s simply not the case. The vast majority of five-point scales force you to allocate 1,2,3,4,or 5 stars. If you thought a product or service was rubbish, you cannot give it zero; that does not count as a rating. As a result the mean score that can be awarded is 3 not 2.5. This is great for retailers who have ratings and reviews on their site as most items will appear to be better than average even when they are not.
2. Self-selection bias in ratings and reviews
There are three kinds of purchase bias that add to “the lie”. The first is self-selection bias. Ask me to rate the restaurant behind my office and I won’t. I’ve never eaten there because I don’t like the way it looks. As a result I have selected myself out of being able to review its food or service.
Thus, ratings and reviews’ second lie comes from the self-selection bias inherent in the need for people to have experienced a product or service before rating it. I know that restaurants which sell all you can eat buffets for £3.50 serve poor quality meat, so I’m not going to buy and I’m not going to review. The people who do review are those who for a given product or service had a reasonable expectation that it would fulfill their needs when making the purchase. Hence the group of potential reviewers is biased from the outset.
3. Choice-supportive bias
The second type of purchase bias comes post-purchase. Choice-supportive bias describes our tendency to recall positive feelings or memories to the choice we made. We tend to remember the positive things about the options we chose more than we remember the positive attributes of the alternatives we did not select.
4. Post-purchase rationalization
The third and final purchase bias is post-purchase rationalisation. This bias comes from our tendency to retrospectively justify our decisions as rational ones. We humans prefer to feel that we made good selections not poor ones. So if you ask me whether or not I liked a product that I just spent my hard earned money on, you’re going to get a positive review more frequently than you get a negative one – we like to feel our past choices have been rational and well made.
It is the sum of these biases that results in an average five-star review of 4.3. That’s a long distance from 2.5.
Despite the lies, Ratings and Reviews are great
I’ve had a bit of a go at Ratings and Reviews, but that does not stop me from liking them. They are excellent tools for online retailers and they do a great service to customers. Just like a review on the back-cover of a book or a politician’s statistics, we should always treat claims with care. And so long as that’s done everyone still stands to benefit. For one thing, if ratings and reviews are considered on a relative basis (as is often the case) then the absolute number does not matter in the least.
And let’s be honest, right now, anything that encourages people to buy more is a good thing for the economy and for all of us.
What do you think?
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Hotels Blogger » FreshNetworks Blog » Blog Archive » The lies behind online ratings …:
[...] the original: FreshNetworks Blog » Blog Archive » The lies behind online ratings … March 27, 2009 • Tags: community, emmanuel-vivier, innovation, series, [...]
27 March 2009, 2:43 pmJoshua Greenough:
I work for PowerReviews.
I will say that 4.2-4.3 is the standard for star rating adjustment and inflation but it actually varies by product category. We provide a solution to let all retailers host reviews on their site for their customers. This is a must have for retailers today for many reasons.
I am responding to this post because we also value trust here at PowerReviews and try to create / push features that enable a well informed community. One feature that we have is staff badging for retailers. This was specifically designed tocurb “Professional Reviews” and we monitor for suspicious reviewers.
Best of luck to all consumers out there and be smart with your shopping because “if it looks too good to be true …” still applies.
Thanks,
1 April 2009, 10:53 pmJoshua
PS. Go to Buzzillions.com for more product review research.
Hoe accuraat is online beoordeling? | Bijgespijkerd:
[...] las afgelopen week een blogpost over online beoordelen. Stelling: Online beoordelingen kloppen niet. Simpel en subtiel… maar toch kloppen ze niet [...]
7 April 2009, 1:55 pmFull Circle Associates » Communities and Networks Connection Hotlists:
[...] The lies behind online ratings and reviews- FreshNetworks, March 27, 2009 [...]
15 April 2009, 1:09 pmTim Uden:
There are some good points here, although I would say that most professional reviewers (particularly those that were reviewing before the internet came along) follow a fairly objective set of standards.
We publish reviews of backpackers hostels and youth hostels.
We have our own staff who visit and rate the hostels and after rating over 1500 hostels we still haven’t given a five star rating.
However we also have user reviews and these tend to be skewed higher than our own ratings and I blame the lack of a zero star rating for this. It is a limitation of our software that I have asked the developers to change, but I doubt it is a big priority for them.
A while ago I contemplated changing from a five star rating system to a percentage-based system but having looked into it, I found that percentage-based systems are skewed toward high ratings much more so than star-based rating systems. I explain why in the following blog post: http://www.bug.co.uk/blog/2009/02/19/why-star-ratings-are-more-accurate-than-percentage-ratings/
5 May 2009, 1:31 amBill Cawley:
I founded Feefo on a simple premise: that the method of feedback pioneered by eBay was, and is, by far the best way to judge the value of service and product offered by a supplier.
At Feefo, we’ve expanded that principle to cover any web trader who is prepared to see every customer make uneditable comment on a public independent website. We’ve also avoided the ’star’ rating system for exactly the reasons you’ve given, and preferred simply to show the percent positive comment, and the number of comments.
This isn’t perfect – the sample is self-selecting; but then every sample is self-selecting insofar as there will always be people who refuse to give time for feedback. We make it very quick, with the result that we have achieved up to 30% response rate (from the entire customer base).
It’s up to those reading the reviews to decide if they mean anything. You can see ALL our reviews on our site.
31 May 2009, 9:48 pmCharlie Osmond:
Thanks Joshua, Tim and Bill,
31 May 2009, 10:21 pmSome useful comments. I suspect there is no perfect solution. People just need to keep their wits about them.
Charlie
Online ratings and reviews are the new advertising | FreshNetworks Blog:
[...] Another reason not to worry about bad reviews is that most people are generous reviewers. See this previous post for more on Why Reviews Lie. [...]
7 September 2009, 12:13 pmSocial Media and the insurance industry | FreshNetworks Blog|Social media agency|Online communities:
[...] payment. As a result, it’s well suited to storytelling and sharing of experiences. Hence ratings and reviews have the potential to be an especially powerful tool for the insurance [...]
18 February 2010, 4:30 pm