The details

This project was funded by the SURE summer studentship scheme run by CILASS at the University of Sheffield. It has ethical approval from the department's ethics committee.

It was run by:

  • Kristian Glenny (second year Psychology and Philosophy student)

  • Anna Galloway (recent graduate, Psychology, BSc (Hons) first class)

  • Tom Walton (graduate and postgraduate student in the department)

  • Tom Stafford (lecturer in Psychology and Cognitive Science)

Do your own tea taste test

Having extolled the virtue and importance of testing our beliefs and biases we strongly suggest you take the tea taste test to where ever you are and let us know your results! You can apply the same method to other things (can you tell the difference between different makes of coke, or different kinds of flapjack for example?). The taste test is a template for one way in which we can investigate if our beliefs are supported by reality, or whether we have allowed spurious beliefs and biases to arise.

Instructions

To create your very own tea taste test all you will need is:

  1. One experimenter

  2. One tea maker

  3. At least one willing participant

  4. A teapot

  5. A kettle

  6. Mugs

  7. Tea bags

  8. Milk

  9. Raffle tickets and a container for them

  10. Two random number lists referring to milk first placement and first cup sampled. These are included at the end of the page.

Experimenter

Before the tea tasting starts it may be useful to explain to those who are taking part why the taste test is relevant to psychology and briefly explain the importance of the original experiment. The experimenter should also ask the first three questions on the questionnaire, which can be found on the website as part of the results section:

  1. If someone were making you a cup of tea, how would you prefer it to be made: milk first; tea first; or does it not matter?

  2. On a scale of 1 to 3, with 1 being not strongly at all and 3 being very strongly, how strongly do you feel about this?

  3. Do you think you could tell the difference between two cups made a different way round?

The experimenter should now allow each participant to pick a raffle ticket from the container. The number needs to be told to the experimenter making the tea .

As each participant is given their two cups of tea you must instruct each individual as to which cup they need to drink from first. This information is found in the random number tables below and achieved by matching the number the participant pulled out from the hat with the one on your list. You should also inform the participants that you need them to think about which cup they preferred and which one they think had the milk added first.

Once the participants have reached a decision they should give their answers to the final two questions, which cup of tea they preferred and which they believe was made with the milk first. Following this the tea maker is then at liberty to reveal to each participant where their milk first was.

The experimenter should then explain what the aim of this experiment was (to test our everyday biases to elucidate whether they are formed on the basis of reality), explain what they expected to find (that there is no difference between the two methods of making tea in terms of taste and so, on average, people are correct only 50% of the time, which is at chance level) and ask if there anyone has questions about the experiment.

Tea maker

The tea maker should choose a location to make the tea that is not directly visible by either the participants or the experimenter in order to ensure a double blind scenario. This way the experimenter cannot affect the choice of the participants and the participants have no idea which cup of tea is made with the milk first and which is made with the tea first.

Once each participant has picked a raffle ticket the tea maker should note down the numbers which the participants pull out. The tea maker must then match each number to one on their list, which tells them on which side to place the cup of tea made with the milk first.

The protocol for making the tea can be decided between the experimenter and the tea maker, but it must remain constant throughout the trials. This is the method we used as part of our experiment:

  • Use one mug full of boiling water for every two cups of tea, one teabag should be used per mug of water.

  • The teabags and boiling water should be left to brew for 4 minutes in a teapot.

  • Next you should stir twice, anti-clockwise.

  • All teabags must be removed before pouring into cups.

  • Milk should be poured from the carton into a marked cup and then into the teacups to ensure equal amounts of milk in every cup.

Once the tea maker has brought the cups of tea over, they should inform the experimenter which cup of tea is the left hand side from the view of the participant. That is, the left in the random number tables refers to the participant's left, not that of the tea maker or the experimenter.

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A note for teachers

This experiment provides an excellent opportunity to discuss some key concepts in scientific investigation, namely single and double blind experiments, controlled conditions, sampling techniques and counter balancing. Throughout the course of the tea tasting the experimenter may feel they are able to explain what these concepts are and why they are so vital to scientific study. A more in-depth explanation of these concepts can be found in 'The Science' section of the website.

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Random number lists

  1. position of milk first cup right

  2. position of milk first cup right

  3. position of milk first cup right

  4. position of milk first cup right

  5. position of milk first cup left

  6. position of milk first cup left

  7. position of milk first cup left

  8. position of milk first cup right

  9. position of milk first cup right

  10. position of milk first cup left

  11. position of milk first cup left

  12. position of milk first cup right

  13. position of milk first cup right

  14. position of milk first cup right

  15. position of milk first cup left

  16. position of milk first cup left

  17. position of milk first cup left

  18. position of milk first cup right

  19. position of milk first cup left

  20. position of milk first cup left

  21. position of milk first cup left

  22. position of milk first cup left

  23. position of milk first cup right

  24. position of milk first cup right

  25. position of milk first cup left

  26. position of milk first cup right

  27. position of milk first cup right

  28. position of milk first cup right

  29. position of milk first cup left

  30. position of milk first cup left

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  1. first cup to taste right

  2. first cup to taste left

  3. first cup to taste left

  4. first cup to taste left

  5. first cup to taste right

  6. first cup to taste right

  7. first cup to taste left

  8. first cup to taste right

  9. first cup to taste left

  10. first cup to taste left

  11. first cup to taste left

  12. first cup to taste left

  13. first cup to taste right

  14. first cup to taste right

  15. first cup to taste right

  16. first cup to taste left

  17. first cup to taste right

  18. first cup to taste left

  19. first cup to taste right

  20. first cup to taste left

  21. first cup to taste left

  22. first cup to taste left

  23. first cup to taste right

  24. first cup to taste right

  25. first cup to taste left

  26. first cup to taste right

  27. first cup to taste left

  28. first cup to taste right

  29. first cup to taste right

  30. first cup to taste right

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