FOR MORE CLASSES VISIT tutorialoutletdotcom MATH 131 Lab 3 8/16 The goal of this lab is to find descriptive statistics for your quantitative data. Part 1: V2, Quantitative Data (3 points) Use the list of all 40 numbers from Lab 1, column V2 for this part of the lab.

1. MATH 131 he goal of this lab is to find descriptive statistics
FOR MORE CLASSES VISIT
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MATH 131
Lab 3 8/16 The goal of this lab is to find descriptive statistics for your
quantitative data.
Part 1: V2, Quantitative Data
(3 points) Use the list of all 40 numbers from Lab 1, column V2 for this
part of the lab.
A. Identify the name of the quantitative variable V2 that you are using
_Peak Position_______.
B. Use StatCrunch or Minitab to find
Mean
Median
Mode
Standard Deviation 7.9
3
1
9.35 Minimum Value
Maximum Value
Q1
Q3 1
33
1
11.75 Descriptive Statistics: Peak Position
Variable
N N* Mean SE Mean StDev Minimum Q1 Median Q3 Maximum Mode
Peak Position 40 0 7.90 1.48 9.35 1.00 1.00 3.00 11.75 33.00 1
C. Using the appropriate numbers from B above, make a box-and-
whisker plot for your data.

2. What does this plot tell you about your data? Boxplot of Peak Position
35 30 Peak Position 25 20 15 10 5 0 1 MATH 131
Lab 3
The data is positively skewed. 8/16 (2 Points) D. Looking at your list in
B, list your Minimum, Maximum and Mean data values. List below and
then find the z-score for each.
Data Value, x z-score ( z= Minimum 1 -0.726 Maximum 33 2.642 Mean
7.9 0 x−´x
)
s E. How do -scores indicate a data value is above the mean?
z
__positive__value___________________.
below the mean? _________negative value________________.
What -score always corresponds to the mean?
________zero___________________.
z
(2 Points) F. Use Chebychev's Theorem to write a statement about the
interval from 2 standard deviations
below the mean to 2 standard deviations above the mean. List the
specific interval you used for
your data. Interpret the result in the context of your data.
Based on chebyshevs theorem, about 75% of the data should be within
two standard deviations from the
mean.
interval for my data
Lower bound= -10.88
Upper bound =26.6
Values within the interval = 36
% of values within the interval = 90%
The data is not consistent with chebyshevs theorem.
Part 2: V3, Quantitative Data
(3 Points)
A. What is the name of your V3 variable? ____Weeks On
Chart________________________
2 MATH 131

3. Lab 3 8/16 B. Fill in the values in the chart below using the frequency
distribution in Lab 2, Part 3. You may not
need all of the rows below.
C. Use the appropriate values in the table to find the mean for your
grouped data.
Show your computations. Remember ∑ (x ∙ f )
´x =
n Data Groups,
using V3 Frequenc
y f Class
Midpoint 1-20
21-40
41-50
51-70
71-90
91-110
111-130
131-150 6
1
3
3
5
8
4
10 10.5
30.5
40.5
60.5
80.5
100.5
120.5
140.5 Total
Mean= x 40
87.25 D. Use StatCrunch or Minitab to find the mean and standard
deviation of the raw data.

4. (from Lab 1).
Descriptive Statistics: Weeks on Chart
Variable
Mean StDev
Weeks on Chart 40 0 77.28 49.64
E. Compare the answers in C and D. What accounts for any difference?
3 x∙f
63
30.5
121.5
181.5
402.5
804
482
1405
3490 MATH 131
8/16
Lab 3
For the frequency distribution, the result is an estimate as compared to
that of the Minitab output which
is exact as it is based on individual scores StatCrunch directions Minitab
directions 1. Stat
2. Summary stats
3. Columns 1. Stat
2. Basic Stat
3. Display descriptive statistics
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