Chapter 1

Question 1

Data

Answer 1

Info such as counts ( how many..?), responses (yes/no), measurements (heights, weights, time length..), and observations (# of touchdowns in a NFL game)

Question 2

Two types of data:

Answer 2

Population & Sample

Question 3

Population

Answer 3

Collection of all outcomes, measurements, responses, etc.

Question 4

Sample

Answer 4

• Subset of a population
  -used to make inference about the population
  -collected by random sampling (to avoid bias)
  -every member of a pop. has an equally likely chance to being selected.

Question 5

Examples of Population Data

Answer 5

1. The age of each member of the House of Representatives
2. The annual salary of each lawyer at a firm

Question 6

Example of sample data

Answer 6

The height of every 4th person entering the amusement park

Question 7

Parameter

Answer 7

A numerical description of a population characteristic

Question 8

Statistic

Answer 8

A numerical description of a sample characteristic

Question 9

Examples of Parameter

Answer 9

1. As of Jan 2012, 60% of the governors of the 50 states in the US are Republican. Parameter=60%
2. For a certain movie, 64.3% of the 112 members of the audience were females. Parameter=64.3%

Question 10

Examples of Statistic

Answer 10

1. The avg annual salary for 35 of a company’s 1200 accountants is $68,000. Statistic=$68,000
2. A survey of 42 out of hundreds in a dining hall showed that 40.5% enjoyed their meal. Statistic=40.5%

Question 11

Two types of Statistics:

Answer 11

Descriptive & Inferential

Question 12

Descriptive

Answer 12

-Organizing, summarizing, and displaying data
-Describes the result of the sample WITHOUT making any general conclusions about the entire population

Question 13

Inferential

Answer 13

-A method that uses a result from a sample to draw conclusions about the entire population, and measures the reliability of the result from the sample

Question 13

Descriptive Statistics Example

Answer 13

In the sample of 1017 men and women. 76% of women and 60% of men had physical exam

Question 13

Inferential Statistics Example

Answer 13

Women seem to be more concerned about their health because a statistic shows that higher percentage of women than men that had a physical exam within the year

Question 13

Two types of variables:

Answer 13

Qualitative and Quantitative

Question 14

Qualitative or Categorical

Answer 14

-Has no numerical values
-attributes, names, labels, ID, SSN, Zip codes, hair color, phone numbers, etc.

Question 15

Quantitative

Answer 15

-has numerical values
-counts
-measurements (of heights, weights, etc)

Question 16

Discrete variable

Answer 16

-Has a finite or countable number of possible values
-0,1,2,3,…
-It cannot take every possible value between two values.
-ex. # of pets, # of TVs, etc. (i.e. counts)

Question 17

Continuous variable

Answer 17

-has an infinite number of possible values (uncountable)
-it can take every value in between two values
-e.g., Measurements of heights, weights, etc.