Chapter 6: The Normal Distribution Pinkie LabStudent Learning Outcomes:
The student will compare empirical data and a theoretical distribution to determine if everyday experiment fits a continuous distribution.
I. Collect the Data1. The lengths of the pinkie finger of 30 adults are given below, to the nearest 0.5 cm.
5 |
5 |
5 |
5.5 |
5.5 |
5.5 |
5.5 |
5.5 |
5.5 |
5.5 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6 |
6.5 |
6.5 |
6.5 |
6.5 |
6.5 |
7 |
7 |
2. Construct a histogram. Make 5 – 8 intervals. Sketch the graph using a
rulerand pencil. Scale the axes.
Stapleyour histogram to this lab. REMEMBER: NO endpoint of an interval is a data value.
3. Calculate the following
- = __________
- s = __________
4.
Drawa smooth curve through the top of the bars of the histogram. Use 1 - 2 complete sentences to
describethe general shape of the curve. (Keep it simple. Does the graph go straight across, does it have a V shape, does it have a hump in the middle or at either end, etc.?)
II. Analyze the DataUsing your sample mean, sample standard deviation, and histogram to help, what was the approximate theoretical distribution of the data?
- X ____________
How
does the histogram help you arrive at the approximate distribution? (Use 1-2 complete sentences.)
III. Describe the DataUsing the data in
Part I:
Remember:IQR = Q3 – Q1
- The IQR goes from ________ to _________.
- IQR = ______.
- The 15th
percentile is _____________.
- The 85th
percentile is ______________.
- The median is ___________.
- The empirical probability that a randomly chosen pinkie length is less than 5.5 cm = _____________.
- Explain the meaning of the 85th
percentile of this data.
IV. Theoretical DistributionUsing the theoretical distribution in
Part II:
- The IQR goes from _____________ to ______________.
- IQR = ___________.
- The 15th
percentile is _____________.
- The 85th
percentile is ______________.
- The median is ___________.
- The theoretical probability that a randomly chosen pinkie length is less than 5.5 cm = _____________.
- Explain the meaning of the 85th
percentile of this distribution.
V. Discussion Question
- Do the data from “Collect the Data” give a close approximation to the theoretical distribution in “Analyze the Data?” In complete sentences and comparing the result in “Describe the Data” and “Theoretical Distribution”,
explain
why or why not.