2022 Introduction to Statistics in Research Mitchell 2nd ed

I N T R O T O R E S E A R C H : D A T A V I S U A L I Z A T I O N & C O M M O N S T A T T E S T S

In general, in any stem-and-leaf display look for

• a representative or typical value (center) in the data set. • the extent to which the data values spread out. • the presence of unusual values (gaps and outliers). • the extent of symmetry in the data distribution • the number of locations of peaks

For this simple data, just a few things to note.

Library Reviews Summer Reading Habits

Descriptive Statistics

Female

Male 30.92 33.50 12.00 50.00 26.00

Mean

33.00 37.50 11.00 50.00 23.25 -.531

Median

Min Max

Interquartile Range

Skewness

.167

Stem-and-leaf

Histograms (Bimodal and Multimodal)

Table 97: Summer Reading Program Summary

Histogram

Use a histogram when you have univariate numerical data. You can use a histogram for either discrete datasets or continuous data sets. An example of a discrete data set would be number of vacations taken by 25 families you surveyed. An example of a continuous data set would be carry- on luggage weight for 25 airline passengers. The end result looks much like a column-chart. When you construct a histogram, look for the

center or typical value

• •

spread

• general shape and location and number of peaks, and • gaps or outliers

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