Is There a Difference Between Dominant and Nondominant Hands

1
Reaction Time

• Is There a Difference Between Dominant and
  Non-dominant Hands?

2
Step One

• Question Is a persons dominant hand faster than
  their non-dominant hand?
• We suspect that the answer is yes.
• So, we need to state the competing theories.

3
Step One

• State Our Hypotheses
• The null hypothesis is
• The alternate hypothesis is
• Decision Rule
• What amount of difference will we consider
  significant?

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Step Two

• Design the study Well take one measurement
  from each hand noting which is the dominant and
  non-dominant hand. Multiple tries for each hand
  may cause some training and bias results. Well
  keep the data as ordered pairs since it is
  matched data.

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Step Three

• Collect the Data It is important that the data
  be collected in such a way that minimizes
  variance and bias. To do this, all subjects need
  to be tested in as similar of a fashion as
  possible.

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Step Three

• Randomly select a hand from the victim to test
  first.
• Select a number at random from 1 to 10 and do not
  let the subject know what it is. Have subject
  hold index finger and thumb close together and
  ask them to keep their eyes on them. Place
  reaction timer so line is just above thumb.
  Silently count to the random number and drop the
  timer. The number closest to where the subject
  grabbed the timer is their time in seconds.

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Step Four

• Analyze the Data Since the data is ordered pair
  data, we can display the data in a scatter plot.
  If there really is no difference in reaction
  time, then the data should all fall very close to
  the line y x. Why?
• Another excellent plot to look at is a
  side-by-side boxplot to compare the distribution
  of the dominant and non-dominant hands.

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Step Five

• State your Conclusions This is where you get to
  voice your conclusions and opinions based upon
  the facts you have observed. It is also where you
  state any flaws that you observed in your
  research and make suggestions for further study.

9
Write Up

• Working in groups of 2 to 4, write up your
  results and post it on the board.