Imagine that the following are iPhone apps.

Each imaginary example has a different combination of brand, rating (in stars) and price.

Review all of the apps and rate each one individually (as if it was the only one available) on a scale of 0 to 100 using the slider:

• A rating of 100 being your most preferred (meaning "I would definitely buy")
• A rating of 0 being your least preferred (meaning "I would definitely not buy")
• Other ratings indicating degrees of like/dislike between these extremes

When you have finished, click Done.

If there are any problems, you can contact me on andrew.clarke09@imperial.ac.uk

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