Lecture 7

Question 1

interval variables

Answer 1

these are variables where the distances between the categories are identical across the range of categories

Question 2

ratio variables

Answer 2

interval variables with a fixed zero point

Question 3

ordinal variables

Answer 3

variables whose categories can be rank ordered (as in the case of interval/ratio variables) but the distances between the categories are not equal across the range.

Question 4

nominal variables

Answer 4

categorical variables, variables that cannot be rank ordered.

Question 5

Dichotomous variables

Answer 5

variables that contain data that only have two categories

Question 6

univariate analysis

Answer 6

refers to the analysis of one variable at a time

Question 7

bivariate analysis

Answer 7

Analysis of two variables at the same time to discover whether or not the two are related

Question 8

pearson’s r

Answer 8

a method for examining relationships between interval/ratio variables (value [-1]-0-1, 0=no relationship, 1 perfect positive relationship etc.)

Question 9

Coefficient of determination r2

Answer 9

expresses how much of the variation in one variable is due to the other variable. The higher it is, the stronger is the correlation between the two variables.

Question 10

multivariate analysis

Answer 10

simultaneous analysis of three or more variables

Question 11

spurious relationship

Answer 11

there appears to be a relationship between two variables but the relationship is not real: it is being produced because each variable is itself related to a third variable.

Question 12

intervening variable

Answer 12

explains the process through which two variables are related.

Question 13

moderating variable

Answer 13

affects the strength and direction of that relationship.

Question 14

test of statistical significance

Answer 14

allows the analyst to estimate how confident he or she can be that the results deriving from a study based on a randomly selected sample are generalizable to the population from which the sample was drawn.

Question 15

null hypothesis

Answer 15

says that the two variables are not related in the population

Question 16

statistical significance

Answer 16

the level of risk that you are prepared to take that you are inferring that there is a relationship between two variables in the population from which the sample was taken when in fact no such relationship exists.

Question 17

when do we reject the null hypothesis?

Answer 17

when the p-value is smaller than the level of significance.

Question 18

type 1 error

Answer 18

rejecting the nut hypothesis when it is true

Question 19

type 2 error

Answer 19

not rejecting the null hypothesis when it is false

Question 20

what are three basic methods for testing hypotheses?

Answer 20

Chi-square, Correlation analysis, regression analysis

Question 21

chi-square test

Answer 21

examines the probability that observed frequencies are randomly distributed of the independent variable

Question 22

what is the chi-square test affected by?

Answer 22

the magnitude of the effect and the number of categories/values of each variable