Chapter 13

Question 0

Analysis of variance

Answer 0

A statistical significance test for determining whether two or more means are significantly different. F is the ratio of systematic variance to error variance.

Question 1

Alpha Level

Answer 1

The probability of incorrectly rejecting the null hypothesis that is used by a researcher to decide whether an outcome of a study is statistically significant ( most commonly, researchers use a probability of .05).

Question 2

Confidence interval

Answer 2

An interval of values within which there is a given level of confidence (e.g., 95%) where the population value lies.

Question 3

Degrees of Freedom

Answer 3

A concept used in tests statistical significance; the number of observations that are free to vary to produce a known outcome.

Question 4

Error Variance

Answer 4

Random Variablility in a set of scores that is not the result of the independent variable. Statistically, the variability of each score from its group mean.

Question 5

Inferential Statistics

Answer 5

Statistics designed to determine whether results based on sample data are generalized to a population.

Question 6

Null Hypothesis

Answer 6

THe hypothesis, used for statistical purposes, that the variables under investigation are not related in the population, that any observed effect based on sample results is due to random error.

Question 7

Power

Answer 7

The probability of correctly rejecting the null hypothesis.

Question 8

Probablity

Answer 8

THe likelihood that a given event ( among a specific set of events) will occur.

Question 9

Research Hypothesis

Answer 9

The hypothesis that the variables under investigation are related in the population-that the observed effect based on sample data is true in the population.

Question 10

Sampling Distribution

Answer 10

Theoretical distribution of the frequency of all possible outcomes of a study conducted with a given sample size.

Question 11

Statistical Signifigance

Answer 11

Rejection of the null hypothesis when an outcome has a low Probablity of occurrence (usually .05 or less) if, in fact, the null hypothesis is correct.

Question 12

Systematic Variance

Answer 12

Variability in a set of scores that is the result of the independent variable; statistically, the variability of each group mean from the grand mean of all subjects.

Question 13

T test

Answer 13

A statistical Signifigance test used to compare differences between means.

Question 14

Type 1 error

Answer 14

An incorrect decision to reject the null hypothesis when it is true.

Question 15

Type II error

Answer 15

An incorrect decision to accept the null hypothesis when it is false.