Lab 12 Knowledge of Results

Statement of the Problem

The purpose  of this lab experiment is to examine the in  uence of speci  c vs. general knowledge  of results (KR) on learning a motor  skill.


Chapter 12

Materials Needed

•   Bean bag

•   Blindfold

•    Circular  bullseye target  (see targets.html for instructions for making a target)

•   Tape

•   Individual  Data Sheet

•   Group  Data Sheet


The objective of this task is to throw  a bean bag while blindfolded so that it lands on the bullseye.

Divide into two groups.  Group  1 (Speci  c KR) receives speci  c KR in terms of where the bean bag hits the target (in relation  to the bullseye). For example,  “You were 6" too long and 8" to the right.”  Group  2 (General KR) receives general KR in the form of what direction  the error occurred.  For example,  “You  missed to the right and long.”

The target should  be placed   at on the   oor 8m from the taped throwing line. Scores are recorded  in the  Individual  Data Sheet according  to the zone in which the bean bag comes to rest, with the inner circle receiving 5 points,  the next zone 4 points,  and so on with the outer ring receiving a score of 1. Any toss not landing on the target receives a score of 0.

You will work in pairs within each group with one performing the task while the other provides KR according  to assigned group,  records the score, and retrieves the bean bag. The thrower stands behind  the throwing line and puts on the blindfold. The thrower then tosses the bean bag towards the target,  using an underhand motion. Each participant receives 15 trials on the task. All trials should be completed  for one participant before you switch roles.


1.  Using your  Individual  Data Sheet, calculate the mean score for the last 10 trials.

2.  Gather  the mean scores from the other participants and record each individual’s score into the  Group  Data Sheet.

3.  Calculate  the group means.

4.  Create a bar graph at to illustrate  the group means.


1.  Was there a difference in accuracy between the two groups?

2.  What do these results suggest about  the specificity of KR?