Chapter 1: Introduction to Business Statistics

Poll Results

Nanos Poll

• As of mid-June 2013, Liberals had the support of 34.2% of voters, Conservatives 29.4%, and NDP 25.3%.
• The article states that Nanos surveyed 816 committed voters and the poll is accurate plus or minus 3.5 percentage points, 19 times out of 20.
• We will have more to say about this statement in Chapter 7 (Confidence Intervals).

"Dewey Defeats Truman" : The picture and the story behind the Harry Truman vs. Thomas Dewey 1948 presidential election. (Did Dewey win?)

Random Digits

A Million Random Digits : RAND Corporation's "A Million Random Digits."

Here's an actual page from the "A Million Random Digits."

MegaStat generates 25 uniform random numbers each in the format 0.xxxxx which is somewhat similar to the page from Million Digits. You just pick any two digits as your random selection.

Here, MegaStat generates 30 random numbers (integers) between 0 and 99.

Real Estate Data

Real Estate Data : This data set  contains 10 variables. For each variable, determine if it is quantitative or qualitative. If quantitative, is it, (i) discrete or continuous, (ii) ordinal, interval or ratio?

¶ Solution :

Price, LotSize, SqrFt, Distance: Quantitative, continuous and ratio.

Bedrooms, Bathrooms: Quantitative, discrete and ratio.

Pool, Basement: Qualitative.

Rating: Seven point scale of a person's rating. This is ratio, but may be just ordinal. To be ratio, 6 would have to be twice as good as 3.

SubDiv: Qualitative.

Summary of Section 1.4 that is relevant to the above example

• Levels of measurement (NOIR)
  • Qualitative variables
    • Nominal (no measurement)
      • Ex. Gender (male/female)
    • Ordinal (ranking)
      • Ex. Prefer Honda to Toyota
  • Quantitative variables
    • Interval (ratio not meaningful and no natural zero)
      • Ex. Celcius vs. Fahrenheit
      • Ex. Rating scales (1 to 7)
    • Ratio  (ratio meaningful and there is a natural zero)
      • Ex. Salary, distance

Actual real estate data for Hamilton homes.

Sampling a Process

Liebeck v. McDonald's Restaurants : The case of the woman (Stella Liebeck) who burned herself with hot coffee at McDonald's and was awarded $640,000.

Coffee Temperatures : Sampling a process.

A personal data set : What is this?