2.76
Activity A:
Get the Gizmo ready:
0.76
2.67
0.67
Feedback vs.
• Click Reset (2).
2.55
0.55
2.54
0.54
no feedback
. A calculator is recommended for this activity.
3.12
0.12
Question: It is possible to view your times as you are doing an experiment. How much
does feedback help when you are estimating time?
1. Predict: How do you think receiving feedback during the simulation will change your results?
Activity A (continued from previous page)
5. Analyze: Select the HISTOGRAM tab. A histogram
shows how many data points fall into each time
interval. You can change the size of the interval using
the # of bins slider. For now, set the slider to 8 bins..
A. Draw the histogram in the space at right.
B. According to the histogram, how many times
were in the 1.5-2.0 second interval? How
many were in the 2.0-2.5 second interval?
1.5-2.0 s:
2.0-2.5 s:
Count
20
15
10
5
Time (5)
0
1
2
3
4
2. Gather data: Select the INSTRUCTIONS tab, and check that the Show statistics checkbox
is not selected. Click Play, and test yourself with 10 clicks. When you are done, select the
TABLE tab and list your times below.
6. Interpret: Select the GRAPH tab. The graph shows the time of each interval between mouse
clicks. Based on the graph, did your ability to estimate time improve over time? Explain
.
3. Calculate: View your results on the TABLE tab.
A. What is the mean (u) of your data set?
B. The range of a data set is equal to the difference between the highest and lowest
values in the set. What is the range of your data?
C. The error is the difference between the actual time and the goal time (2 seconds). In
the Gizmo, the absolute values of the errors are given.
What are the highest and lowest errors in your data set?
D. Percent error is a measure of relative error. It is used to compare the errors when
you are approximating two different values. To calculate percent error, divide the
error by the goal time and multiply by 100.
What are your highest and lowest percent errors?
4. Calculate: Now, calculate the mean (average) error and mean (average) percent error for
your data. (Hint: To calculate the mean error, add up all of the errors and divide by 10.)
Mean error:
Mean percent error:
Check your calculations by turning on Show statistics.
(Activity A continued on next page)
7. Gather data: Click Reset. Select either the TABLE, HISTOGRAM, or GRAPH tab for
feedback. Click Play and run the experiment until you have 10 clicks. List the times below.
8. Calculate: Determine the following values, and then check your answers using the Gizmo.
Mean % error:
Mean:
Range:
Mean error:
9. Analyze: Look at the histogram and graph of this experiment.
A. How did your ability to estimate time change when you had feedback?
B. Why do you think having feedback affected your ability to estimate time in the way
that it did?