Pair up.  One of you toss a coin 10 times.  The other record on a small piece of paper how many time...
Sponsored Links
This presentation is the property of its rightful owner.
1 / 17

Today’s session PowerPoint PPT Presentation


  • 64 Views
  • Uploaded on
  • Presentation posted in: General

Pair up. One of you toss a coin 10 times. The other record on a small piece of paper how many times it comes up ‘heads’. When you have recorded 10 results, give the paper to me. Repeat until I ask you to stop. Today’s session.

Download Presentation

Today’s session

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


  • Pair up. One of you toss a coin 10 times. The other record on a small piece of paper how many times it comes up ‘heads’. When you have recorded 10 results, give the paper to me. Repeat until I ask you to stop.


Today’s session


  • Unlike much of what you are used to in the physical sciences, judgements in psychology are often based on probability


  • When you toss a coin, what is the probability it will come up ‘heads’?

  • If you have thrown nine heads in a row, what happens to the probability that your next toss will be ‘heads’?


  • If we plot the results from your earlier coin tosses on the graph below, what shape will we get?

5 heads; 5 tails

O heads; 10 tails

10 heads; 0 tails


Normal distribution curve

Likely outcomes

Unlikely outcomes

5 heads; 5 tails

O heads; 10 tails

10 heads; 0 tails


  • Does your partner have telekinetic powers?

    • Decide who will be the researcher and who will be the participant.

    • Participant will use the power of their mind to will the coin to come up ‘heads’


  • If your participant’s coin came up heads, does that mean she has telekinetic powers?

  • So how can we use coin tosses to test if she does?


Unlikely to be caused by chance; perhaps caused by something else

Likely to be caused by chance

5 heads; 5 tails

O heads; 10 tails

10 heads; 0 tails


  • How many times out of ten must the participant’s coin come up heads before we accept that the result was not just due to chance?


  • Did any participant meet or exceed the criterion?

    • Does this (or would this) prove that she had telekinetic powers?

    • What would we do to check?


Significance

  • In psychological research we judge the importance of results by comparing them with what is likely to happen by chance.


  • Everyone choose a number between 1 and 10 and write it down

  • We’ll divide the class arbitrarily in half and compare the numbers they have chosen

  • Do we expect that the two sets of numbers will be very different?


  • The two sets of numbers will not be identical; they will be different. However:

    • The difference may be due to chance

    • The difference may be due to something else


  • Let’s repeat the test. This time, read what’s on the card before choosing your number.


Significance

  • The more consistent the difference between the two sets of numbers, the smaller the probability that the difference was caused by chance.

  • However, we have to decide how unlikely a ‘chance result’ has to be before we will accept that the difference was caused by something else


Significance

p0.05


  • Login