Pitter Patterns
What is a cluster in a box plot?
A group of data points that lie within a small interval.
Prices of Jeans:
$35, $28, $42, $50, $24, $75, $47, $32, $60
What is the median of the data?
$42
What is mean absolute deviation?
The mean distances of data value from the mean of the data set.
What is a measure of variability?
A single value used to describe how spread out the data values are.
How does an outlier affect your data?
It makes it increase or decrease more than what it should actually be.
Describe when a graph has symmetry:
If you can draw a line through it so that the two sides of the graph are almost mirror images of each other.
Prices of Jeans:
$35, $28, $42, $50, $24, $75, $47, $32, $60
What are the lower quartile and the upper quartile values?
$30 and $55
First find the mean of the data. Then look at how far away your data values are away from the mean. Find the mean of that data.
30, 42, 68, 100, 120
90
Thomas is writing an article for the school newspaper about a paper airplane contest. In the distance category, Kara's airplanes flew: 17ft, 16ft, 18ft, 15ft, and 2ft. Should Thomas use the mean, median, or mode to best describe Kara's results? Explain your reasoning.
Mean: 13.6
Median: 16
Mode: None
Median because it is closer to the other values in the data set.
Meg makes a dot plot for the data 9, 9, 4, 5, 5, 3, 4, 5, 3, 8, 8, 5. Where does the gap occur?
6-7
The scores of 11 students on a geography quiz:
87, 72, 80, 95, 86, 80, 78, 92, 88, 76, 90
What is the median, lower quartile and upper quartile of the data?
Median: 86; LQ: 78; UQ: 90
What is the mean absolute deviation of the values:
8, 8, 8, 8, 9, 10, 10, 10, 12, 12, 12, 13
MAD: 1.5
What is the interquartile range of the data? (Hint - these are the values that would be the box plot)
30, 42, 68, 100, 120
58
Mr. Tobin is buying a book online. He compares prices of the book at several different sites. The values show his results. Which measure best describes the data - range or IQR? Explain your reasoning.
15, 35, 17, 18, 5, 16, 17
Range: 30
IQR: 3
IQR range because five of the seven values are inside the IQR; the range makes it seem like it varies more than what it does.
What clusters would a dot plot contain if it had the values: 14, 14, 14, 10, 15, 15, 16, 15, 11, 16, 19, 16, 18, 18, 11, 18?
10-11, 14-16, 18-19
The scores of 11 students on a geography quiz:
87, 72, 80, 95, 86, 80, 78, 92, 88, 76, 90
Create a box plot for the data above.
Lowest: 72; LQ: 78; Median: 86; UQ: 90; Highest: 95
What is the mean absolute deviation of the value:
5, 6, 6, 8, 10
MAD: 1.6
The following data set gives the amount of time, in minutes, it took five people to cook a recipe. What is the mean absolute deviation for the data?
33, 38, 31, 36, 37
3.6
The distance in miles students travel to get to school are: 7, 1, 5, 9, 9 and 9. Decide which measure(s) of center best describe the data set. Explain your reasoning.
Mean, median and/or mode
Mean: 6.5
Median: 7.5
Mode: 9
Median, because the mean is less than 4 of the 6 data values and mode only describes 2 of the 6.
What interval in the history would have the greatest frequency?
Intervals: 0-4, 5-9, 10-14, 15-19, 20-24
Data: 3, 4, 6, 7, 10, 11, 12, 12, 12, 14, 15, 15, 15, 15
10-14
The data shows the height of trees in a park. Display the data in a box plot:
8, 12, 20, 30, 25, 18, 18, 8, 10, 28, 26, 29
Lowest: 8; LQ: 11; Median: 19; UQ: 27; Highest: 30
What is the mean absolute deviation of the values:
1, 3, 7, 11, 13
with a mean =7
MAD: 3.8
The prices of six food processors are 63, 59, 72, 68, 61, and 67. What are the range, IQR, and MAD for the data?
Range: 13
IQR: 7
MAD: 4
Eight students were absent the following number of days in a year: 4, 8, 0, 1, 7, 2, 6 and 3. Decide if the ranger or interquartile range better describes the data set and why.
Range: 8
IQR: 5
IQR because it fits with more of the data points