{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Slides-02 - ECON1203/ECON2292 Business and Economic...

This preview shows pages 1–8. Sign up to view the full content.

Click to edit Master subtitle style ECON1203/ECON2292 Business and Economic Statistics Week 2

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
22 Week 2 topics l Measures of central tendency or location l Measures of dispersion or spread l Measures of association l Introduction to linear regression l Key references l Keller Chapter 4, especially 4.1-4.4
33 Numerical summaries of key features l Previously used graphical methods to summarize data l Can also use numerical summaries of sample or population data l Key features of a single variable l Location, spread, relative standing, skewness l Key feature of two variables l Measures of (linear) association

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Measures of location l A parameter describes key feature of a population l A statistic describes key feature of a sample l A natural measure of location is the arithmetic mean l Other variants l Weighted mean (WAM) l Geometric mean 44
55 Measures of location… l Median is middle value of ordered observations l When n is odd median will be unique l When n is even average middle two values l Median depends on ranks of observations l Doubling largest observation will not change median

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
66 Measures of location… l Mode is most frequently occurring value(s) l Modal class previously defined in context of unimodal histograms l Mean, median & mode all provide different notions of “representative” or “typical” central values l For quantitative data mode usually not a very useful measure of location l What about mean vs. median? Depends l For symmetric distributions mean=median l When positively (negatively) skewed mean > (<) median l Median may be preferred when outliers appear in data
77 Outlier...s l A Malaysian man was speechless when he received a \$218 trillion phone bill and was ordered to pay up within 10 days or face prosecution... It wasn't clear whether the bill was a mistake...

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern