deck_7806227

Question 1

Variable (Definition)

Answer 1

a characteristic that can vary in value among subjects in a sample or population.

Question 2

Categorical Variable (Qualitative)

Answer 2

scale for measurement is a set of categories.Examples:Racial-ethnic group (white, black, Hispanic)Political party identification (Dem., Repub., Indep.)Vegetarian? (yes, no)Happiness (very happy, pretty happy, not too happy)GenderReligious affiliationMajor

Question 3

Nominal Scale

Answer 3

A type of Categorical Variable with unordered categories.Examples:Preference for President, Race, Gender,Religious affiliation, MajorOpinion items (favor vs. oppose, yes vs. no)

Question 4

Ordinal Scale

Answer 4

A type of Categorical Variable with ordered categories.Examples:Political ideology (very liberal, liberal,moderate, conservative, very conservative)Anxiety, stress, self esteem (high, medium, low)Mental impairment (none, mild, moderate, severe)Government spending on environment (up, same,down)

Question 5

Quantitative Variable (Definition)

Answer 5

A set of possible values is called an interval scale (i.e. numerical interval between each possible pair of values) The difference between values are consistent:-Moving from $20,000 to $21,000 is the samemagnitude as moving from $50,000 to $51,000-Moving from 90 degrees F to 95 degrees F is thesame as moving from 70 to 75

Question 6

Skewed Distribution (Describe)

Answer 6

Mean is drawn in direction of longer tail, relative to the median.

Question 7

The following is an example of: e.g., Grades A,B,C,D,E an ordinal scale, buttreated as interval if assign scores 4,3,2,1,0 toconstruct a GPA)

Answer 7

Note: In practice, ordinal categorical variables oftentreated as interval by assigning scores

Question 8

What is Descriptive Statistics?

Answer 8

1. Describing data with tables and graphs(quantitative or categorical variables)2. Numerical descriptions of center(mean/median) and variability (standarddeviation/ variance) (quantitative variables)

Question 9

Frequency distribution

Answer 9

Lists possible values of variable and number of times each occurs. = 60)Ex. Student survey (n “political ideology” measured as ordinal variablewith 1 = very liberal, …, 4 = moderate, …, 7 =very conservative

Question 10

Histogram

Answer 10

Bar graph of frequencies or percentages.

Question 11

Bell-shaped Histogram