Annocement

1
Annocement

• Homework 4 (consists of problems 3.6, 3.8, 3.14,
  3.20, 3.22, 3.24, 3.30, 3.52, 3.56, and 3.60 ) is
  due Friday (Oct. 12) in Lecture or in drop box on
  122 Cockins Hall by 200pm Friday.
• Exam 1 next Friday 10/19/1007 in lecture.

2
Outline

• Graphical summary for quantitative variable
• Dot plot
• Frequency Distribution Histogram
• Stem-and-leaf plot
• Key words when you comment
• Center what is a typical value, most value
  between,
• Spread quite a bit of variability? Range of the
  data
• Shape symmetric? Skewed to right/left? Unimodal?
• Outliers

3
Problem Solving-Chapter 3

• 3.7 Students in California are required to pass
  an exit exam in order to graduate from high
  school. The pass rate for San Luis Obispo High
  School has been rising, as have the rates for San
  Luis Obispo County and the state of California.
  The percentage of students that passed the test
  was as follows
• Year District
  Pass Rate
• 2002 San Luis Obispo High School
  66
• 2003
  72
• 2004
  93
• 2002 San Luis Obispo County
  62
• 2003
  57
• 2004
  85
• 2002 State of California
  32
• 2003
  43
• 2004
  74
• _____________________________________________
  _________

4
Questions

• a. Construct a comparative bar chart that allows
  the change in the pass rate for each group to be
  compared.
• b. Is the change the same for each group? Comment
  on any difference observed.

5
Answers for 3.7 b)

• The pass rate increase each year for San Luis
  Obispo High school and the state of CA from 2002
  to 2004 with a sharp rise in 2004.
• However, in San Luis Obispo County, there was a
  drop in the pass rate in 2003, followed by a
  sharp increase in 2004 when a pass in the exam
  was need for graduation.

10/11/2007
245 Recitation TADongmei Li
6
Problem Solving-Chapter 3

• 3.10 A survey of 1001 adults taken by Associated
  Press---Ipsos asked How accurate are the weather
  forecasts in your area?. The responses are
  summarized in the table below.
• ________________________________
• Extremely
  4
• Very
  27
• Somewhat
  53
• Not too
  11
• Not at all
  4
• Not sure
  1
• a. Construct a pie chart to summarize this data.
• b. Construct a bar chart to summarize this data.
• c. Construct a stacked bar chart to summarize
  this data.
• d. Which of these charts--- a pie chart or a bar
  chart best summarizes the important information?
  Explain.

7
Answers to 3.10 d)

• Both graphs clearly show that Very and
  somewhat are the top two categories. However,
  as the answer choices have an order, it is easier
  to see in the bar chart that the popular answers
  are in the more favorable end of the categories.

10/11/2007
245 Recitation TADongmei Li