1 / 7

Descriptive Statistics: Measures of Center and Dispersion

Learn about mean, median, mode, range, variance, and standard deviation. Explore linear transformations and their effects on data analysis. Includes practice exercises and homework problems.

tlund
Download Presentation

Descriptive Statistics: Measures of Center and Dispersion

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Math 341 January 25, 2007

  2. Descriptive Statistics • Measures of Center • Mean – average {2.5, 3.2, 3.2, 3.4, 3.6, 3.7, 3.9, 3.9, 4, 4.2, 4.2} • Median – middle value • Mode – most frequent occurring value. • Practice – Hospital length of stay → sample size, n=21

  3. Length of Stay {1, 1, 2, 3, 4, 5, 5, 6, 6, 7, 9, 9, 9, 10, 12, 13, 13, 15, 18, 24, 28}

  4. Section 1.4 • Consider 3 samples • {1,2,5,5,8,9} • {3,4,5,5,6,7} • {5,5,5,5,5,5} • Measures of Dispersion (Spread) • Range • Variance • Standard Deviation • Five-number summary

  5. Linear Transformation • Xnew = a + bX • Effect of Linear Transformation • Multiplying each observation by b multiplies both measures of center (mean and median) and measures of spread by b. • Adding the same number a to each observation adds a to measures of center and quartiles but does not change the spread.

  6. Homework Exercises: Sec 1: 4, 7, 8, 9. (pp. 10-11) Sec 2: 10, 11, 15, 18, 20, 25*, 29. (pp.23-28) Sec 3: 34, 36, 41, 42. (pp.34-36) Sec 4: 44, 51, 54, 56, 58. (pp.44-47) Supp: 78, 79. (pp.48-51)

  7. Thank you!

More Related