Lab 8a Modeling and Verbal Instructions

Statement of the Problem

The purpose  of this lab experiment is to examine the effects of providing  a demonstration of a skill in the presence and absence of verbal instructions.


Chapter 8

Materials Needed

•   One piece of rope or string 1 to 1.5 feet in length for each pair of students

•    Instructional video for tying a bowline knot as shown on YouTube:

•   Individual  Data Sheet

•   Group  Data Sheet


The objective of this task is to tie a correct bowline knot. Divide into two groups.  Group  1 (Model  Only) will watch the instructional video for tying a bowline knot with the sound  turned  off. Group  2 (Model  + Verbal Instructions) will watch the same video with the sound turned  on. You will work in pairs within each group,  with one partner performing the task while the other records the number  of correctly performed task components during each trial; use the  Individual  Data Sheet. The  rst participant should complete all trials before partners switch roles.


1.  On the  Individual  Data Sheet, add the total number  of components that you performed correctly for each trial. Calculate  the mean number  of correct components by dividing the total number  of correct components across trials by the number  of trials (10).

2.  Obtain the data on the total  number  of correct  components across the ten trials from all the participants in Groups  1 and 2 and enter it in the  Group  Data Sheet.

3.  Calculate  the mean number  of correct components per participant by dividing the total  number  of correct  components across trials by the number  of trials (10).

4.  Perform a t-test using the mean data of groups 1 and 2 at


1.  How did the verbal instructions affect performance?

2.  Discuss the task sheet used for measuring  performance. How would you change it? Why?

3.  Reexamine  the data.  Who outperformed whom―the individuals  who served as experimenters/recorders   rst or those who attempted the task rst? Why might this have occurred?