Mean, median, mode, range, and outliers
Find the mean of the following set of data: 13, 23, 21, 20, 21, 24, 18
What is the mean is 20
What is the shape of the box-and-whisker plot if the left whisker is longer?
Skewed Left
Give the 5 number summary for: 7, 1, 0, 4, 8, 3, 10
0 (least value)
1 (lower quartile)
4 (median)
8 (upper quartile)
10 (greatest value)
Qualitative or quantitative?
Types of flowers in a flower shop.
Qualitative
Maximum - minimum
Range
What is the mode: 10, 9, 4, 4, 8, 8, 8, 4, 7, 6, 11, 14, 27
What is 4 and 8
What is the shape of the box-and-whisker plot if the right whisker is longer?
Skewed Right
Find the interquartile range for the data set: 12, 14, 11, 10, 9, 10, 9
What is the IQR = 3
12-9 = 3
Qualitative or quantitative?
Lengths of videos on a website.
Quantitative
A graph used to show the distribution of numerical data. It looks somewhat like a bar graph, but displays frequencies of numerical data over equal, continuous intervals.
Histograms
Find a possible missing value in the set of data if the range is 20. 14, 8, 17, 21, ____, 11, 3, 13
What is 1 or 23
What is the shape if the whiskers are about the same length?
Symmetrical
A solution used to kill bacteria is tested The solution kills the following percentages of bacteria in six trials: 85, 84, 87, 86, 90, 80 Use the data to make a box-and-whisker plot.
What is your box-and-whisker plot should have the following points: 80 (least value) 84 (lower quartile) 85.5 (median) 87 (upper quartile) 90 (greatest value)
Qualitative or quantitative?
Telephone numbers in a directory
Qualitative
Quartile 3 - Quartile 1
Interquartile Range (IQR)
Frank has 3 nickels, 5 dimes, and 2 quarters. Find the mean, median, mode and range of the values of Frank's coins.
What is: mean: 11.5 cents median: 10 cents mode: 10 cents range: 20 cents
If most of the data is on the right, and the tail extends to the left, what is the shape called?
Skewed left
Find the interquartile range, round to the nearest tenth if necessary: 5, 2, 4, 7, 4, 4, 1
What is 3
IQR = 5-2 = 3
Qualitative or quantitative?
Heights of skyscrapers in the city.
The ratio of a joint frequency to the total number of values or observations.
joint relative frequencies
Given the data set: 14,13,2,15,13,12,14,13
Prove mathematically that 2 is an outlier.
Q1=12.5, Q3=14, IQR = 14-12.5 = 1.5
Q1 - 1.5(IQR) Q3 +1.5(IQR)
12.5- 1.5(1.5)=10.25 14 + 1.5(1.5)=16.25
2 is less than 10.25
If most of the data is on the left, and the tail of the graph extends to the right, what is the shape called?
Skewed right.
If the median and range are the best measure of center and spread, is the data symmetrical or skewed?
Skewed.
How might a graph be misleading?
No title.
Unequal scale.
Not starting at zero nor showing a break.
Conditional relative frequency