Statistics
Statistics Vocabulary Mean: Average; add all the numbers in the data set, then divide by the amount of numbers in the set. Median: Middle number in a data set when the numbers are arranged in order from least to greatest. Mode: The number in the data set that occurs most often; can have more than 1 mode. Range: The largest number in the data set minus the smallest number in the data set. Outlier: The number that is far away from the majority of data; usually skews the mean.
Stem & Leaf Plots Stem: the 1st digit in a term Put the stem in the 1st or center column in order from least to greatest, vertically. Leaf: the 2nd digit in a term Order from least to greatest working from left to right; if a number occurs more than once, write it more than once. Key/Legend: tells the reader the values of the numbers in the plot.
Stem & Leaf Plots Data Set: Key: 3 1 = 31 1 0 0 5 2 0 1 1 3 3 1 2 10, 15, 20, 21, 23, 49, 32, 44, 31, 10, 21 Key: 3 1 = 31 Make sure the number of leaves match the amount of original data. Stem Leaf 1 0 0 5 2 0 1 1 3 3 1 2 4 4 9
Stem & Leaf Plot Mean = _________ Median = ________ 1 0 0 5 2 0 1 1 3 Mode = _________ Range = ________ Stem Leaf 1 0 0 5 2 0 1 1 3 3 1 2 4 4 9
Stem & Leaf Plot Find the mean, median, mode, and range for the given data. City Highway 9 1 9 8 3 3 0 2 7 8 4 1 1 3 0 2 2 7 8 8 4 1 City Highway Mean Median Mode Range Legend Means 20 MPG 0 2 7 Means 27 MPG
Stem & Leaf Plots Find the difference in the mean for the city and highway. _________________ What is the average gas mileage for driving in the city and highway? City Highway Mean Median Mode Range
Box & Whisker Plot Box & Whisker Plot: Used to display a set of data so you can easily see where most of the numbers are. Quartile 1 Quartile 2 Quartile 3 Quartile 4 25% 25% 25% 25% Minimum Lower Quartile Range Median Upper Quartile Range Maximum 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
Box & Whisker Plots Steps to create a Box & Whisker Plot Write your data in order from least to greatest. Draw a number line that includes all of the numbers in your data. Find the Median Find the Lower Quartile Range Find the Upper Quartile Range Make a vertical line at the median, lower quartile range, upper quartile range and make a box. Plot the minimum and maximum; connect to the box with a line.
Box & Whisker Plot Suppose you caught 13 fish in a lake and measured each one. The lengths in inches are as follows: 12, 13, 5, 8, 9, 20, 16, 14, 14, 6, 9, 12, 12. Mean = _________ Median = __________ Mode = _________ Range = ___________ Outlier = ________ 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Box & Whisker Plots Calculator Steps: Press STAT then ENTER (Which is the EDIT category) and input your data. Press 2nd then y= and press ENTER twice. Highlight the box & whisker picture. Press TRACE. Scroll to find the values of each quartile boundary.
Box & Whisker Plots How many pairs of shoes do you own? 28, 26, 19, 20, 15, 5, 3, 10, 15, 7, 8, 5 Mean = _________ Median = __________ Mode = _________ Range = ___________ Outlier = ________ 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
Box & Whisker Plots Find the mean, median, mode, range, and outlier for the ages of the given family members: 15, 16, 12, 21, 42, 43, 16, 50, 54, 30, 35, 16, 50, 47, 5 Mean = _________ Median = __________ Mode = _________ Range = ___________ Outlier = ________ 5 8 11 14 17 20 23 26 29 32 35 38 41 43 46 49 52 55
Box & Whisker Plots Team 1 Team 2 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 Which team has the highest median? _________________ What’s the difference in box range from Team 2 to Team 1? _______________________ Which team has the lowest range? ___________________