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

Other things provided by Statistics Kingdom:

1) This box plot shows a longer right whisker, so it is positively skewed. You can also tell this from the 1.161327 (positive number here means positive skew).

2) Notice that 50% of the data falls within Q1 and Q3.

If you have an outlier, what do you do about it?

The first thing -search for the cause of the variation. If there is an identifiable, assignable cause that makes the data not representative, then it is reasonable to drop the observation and redo the analysis; you should note it in your report.

Table 60: Information on box plot for school C from Statistics Kingdom

One caveat: Boxplots convey information about center, variability, and shape. But if your sample size is small, interpreting the shape information is a problem.

Finding Data for Practice

There are a ton of sites with data. Here are just a few to get you started.

1) United States Census: http://www.census.gov

2) Statistics Canada: http://www.statcan.gc.ca/start-debut-eng.html

3) Pew Research Center: http://www.pewresearch.org/data

4) Dataverse Network: : http://thedata.harvard.edu/dvn This is a large repository of data created by the Institute for Quantitative Social Science at Harvard University (IQSS).

5) Monitoring the Future: http://www.icpsr.umich.edu/icpsrweb/ICPSR/studies/20022

6) Data Science Central: https://www.datasciencecentral.com/profiles/blogs/big-data-sets- available-for-free

7) General Social Survey (GSS): http://gss.norc.org Data and codebook available for the General Social Survey that is used to assess demographics and attitudes of U.S. residents.

8) Gallop- Global Datasets for Public Use: https://www.gallup.com/analytics/318923/world- poll-public-datasets.aspx

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