Chapter 10 Hypothesis testing and inferential statistics

Question 1

Null hypothesis

Answer 1

the assumption that no real difference exists between conditions in an experiment or that no significant relationship exists in a correlational study

Question 2

alternative hypothesis

Answer 2

the researchers hypothesis about the outcome of the study

Question 3

alpha level

Answer 3

the probability of making a type one error- the significance level

Question 4

type 1 error

Answer 4

rejecting the null hypothesis when it is true. finding a statistically significant effect when no true effect exists

Question 5

Type 2 error

Answer 5

Failing to reject the null hypothesis when it is false. Failing to find a statistically significant effect when the effect truly exists

Question 6

systematic variance

Answer 6

variability that can be attributed to an identifiable source, either the systematic variation of the independent variable or the uncontrolled variation of the confound

Question 7

error variance

Answer 7

non-systematic variability in a set of scores due to random factors or individual scores

Question 8

file-drawer effect

Answer 8

a situation in which findings of no difference are not published. If the number of such findings is large, the few studies that do find a difference and are published, produce a distorted impression of actual differences

Question 9

effect size

Answer 9

amount of influence that one variable has on another- the amount of variance in the dependent variable that can be attributed to the independent variable.

Question 10

meta-analysis

Answer 10

a statistical tool for combining the effect size for the number of studies to determine if general patterns occur in the data

Question 11

confidence interval

Answer 11

an inferential statistic in which a range of scores is calculated with some degree of confidence, it is assumed that population values lie within the interval

Question 12

power

Answer 12

the probability that a test will reject a false null hypothesis