1. 1: Analyzing Categorical Data
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The 1.5 x IQR Rule for Outliers Call an observation an outlier if it falls more than 1.5 x IQR above the third quartile or below the first quartile. The Five-Number Summary The minimum and maximum values alone tell us little about the distribution as a whole. Likewise, the median and quartiles tell us little about the tails of a distribution. To get a quick summary of both center and spread, combine all five numbers. The five-number summary of a distribution consists of the smallest observation, the first quartile, the median, the third quartile, and the largest observation, written in order from smallest to largest. Minimum Q1 Median Q3 Maximum Boxplots (Box-and-Whisker Plots) The five-number summary divides the distribution roughly into quarters. About 25% of the data values fall between the minimum and Q1 About 25% of the data values fall between Q1 and the median About 25% of the data values fall between the median and Q3 About 25% of the data values fall between Q3 and the maximum This leads to a new way to display quantitative data, the boxplot. How To Make A Boxplot: 
A central box is drawn from the first quartile (Q1) to the third quartile (Q3). A line in the box marks the median. Lines (called whiskers) extend from the box out to the smallest and largest observations that are not outliers. Outliers are marked with a special symbol such as an asterisk (*). 
Note: Boxplots show less detail than histograms or stemplots, so they are best used for side-by-side comparison of more than one distribution, as in Figure 1.19. As always, be sure to discuss shape, center, spread, and outliers as part of your comparison. For the travel time to work data: Directory: ourpages -> auto -> 2017 2017 -> Senior Division Solutions 2017 -> Avant garde adademy of broward 2017 -> Have you always wanted to go to space camp? Dreamt of becoming an astronaut here’s your chance! 2017 -> Atlanta, georgia-april 2017-a total solar eclipse occurs when the moon lines up between the earth and the sun-an extremely rare and beautiful event 2017 -> United states history and geography unit 1: The Rise of Industrial America 1877-1914 2017 -> Out-of-Field Notification to Parents/Guardians English 2017 -> Modern History Notes 9-21-2017 Entertainment 2017 -> The secret of change is to focus all of your energy, not on fighting the old, but on building the new 2017 -> The Berlin Conference 1884 Simulation Historical Context 2017 -> Island Biogeography and Biodiversity Part I: Background Reading Download 10.83 Mb. Share with your friends:
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