1| M a th 1 5 30 P roj e ct # 2
Name:
.
⁄𝟐𝟎
𝑆𝑐𝑜𝑟𝑒 =
Date: _____________________________
Preparation:
1) While in Pearson MyLab, on the left Tabs Select Statcrunch –> Visit the Statcrunch website –> Open Statcrunch
2) Click Data – Select Load – From file – on my computer
3) On the new window click on Browse – Select the file “Appalachia Data Set” (from where you saved it)– Click Open.
4) Scroll down and click the drop-down box under Delimiters and select Tab instead of Comma.
5) Scroll down to the bottom of the page and click Upload.
Getting Min & Max values:
a) Click Stat – select Summary Stats - Columns
Hold Ctrl to select both
b) Under Select column(s): – select % completing HS; Under Statistics: – select Min & Max- Click Compute
c) Assuming you want to have 8 classes, use the given formula to approximate the desired minimum class width
𝑐𝑙𝑎𝑠𝑠 𝑤𝑖𝑑𝑡ℎ =
max value − min value
8
This formulas guarantees that all data values will be included in the classes formed!!
[1 pt] Class width = ________________ Round up to next integer!!
Frequency
Task 1: Construct a histogram of the percent of high school completion data:
a) Click Graph – select Histogram
b) Under Select column(s): – select % completing HS
c) Under Bins: – Start at = 55.0; width = enter class width (from above)
d) Under Display options check the box next to Value above bar - Click Compute
e) [4 pts] Sketch the histogram below.
130
120
110
100
90
80
70
60
50
40
30
20
10
55
[1 pt each]
60
65
70
75
80
85
90
95
High School Completion Rate
1) Describe the shape of this distribution using proper statistical terminology (Left/right skewed or Bell-shaped/normal).
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2) Based on the histogram, determine the median class (class containing the median value.)
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3) Based on the histogram, determine the modal class (class with highest frequency.)
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4) Based on the histogram, how many high schools have a completion rate less than 80%?
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5) Based on the histogram, how many high schools have a completion rate between 75% and 95%, inclusive?
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2| M a th 1 5 30 P roj e ct # 2
Name:
.
Task 2: Construct a frequency distribution table of the percent of high school completion data.
Now prepare a frequency distribution for the percent of high school completion for the counties in Appalachia.
Using a given first class limits and the class width, determine the 8 classes for the distribution:
Hint: Use the histogram (Task 1) to determine the frequencies. After finding the frequencies, calculate the relative freq.
[8 pts]
Class
Frequency
Relative Frequency (Round answer to 3 decimals THEN change to % )
55.0 – 59.9
Task 3: Construct a scatter plot of
1)
2)
3)
4)
Click Graph – select Scatter Plot
Under X variable: – select poverty rate; Under Y variable: – select % completing HS
Under Overlay polynomial order: – select 1- Click Compute
[1 pt] Does there appear to be a linear relationship between poverty rate and % of high school completion.
Yes Positive correlation
Yes Negative correlation
No correlation
Describe the relationship between these variables
(ex. what happens to % of high school completion when poverty rate increase):
[1 pt] ______________________________________________________________________________________
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