Neas-Seminars

Fox Module 3: Univariate displays HW


http://33771.hs2.instantasp.net/Topic8666.aspx

By NEAS - 12/3/2009 12:23:01 PM

Module 3: Univariate displays

 

(The attached PDF file has better formatting.)

 

Homework assignment: stem and leaf display

 

A stem and leaf display for assault rates in the fifty U.S. states appears below. The assault rates range from 4.5% to 33.7%.

 

   4 | 568

   5 | 367

   6 |

   7 | 2

   8 | 136

   9 |

  10 | 2699

  11 | 035

  12 | 000

  13 |

  14 | 59

  15 | 1699

  16 | 1

  17 | 48

  18 | 8

  19 | 0

  20 | 14

  21 | 1

  22 |

  23 | 68

  24 | 99

  25 | 2459

  26 | 3

  27 | 69

  28 | 5

  29 | 4

  30 | 0

  31 |

  32 |

  33 | 57

 


A.   What is the median assault rate? There are 50 states, so average two points.

B.   What is the lower hinge (the 25th percentile)?

C.   What is the upper hinge (the 75th percentile)?

D.   What is the value of (HU – Median) / (Median – HL), where  HU is the upper hinge and HL is the lower hinge?

E.   This ratio indicates the skewness of the distribution. Is this distribution positively skewed or negatively skewed?

 

By wb_munchausen - 5/25/2011 8:33:08 AM

NEAS, is the 197 in the equation 197-49+1=149 (p. 39, midpage) a typo?  I thought it should be 193, since n = 193.

[NEAS: Yes, it looks lke a typo.]