week2. 1-way ANOVA

Question 1

what are t-tests used for

Answer 1

to examine differences between two groups/conditions

Question 2

what test are ANOVA’s an extension of

Answer 2

t-tests

Question 3

are t-tests parametric or non parametric

Answer 3

parametric

Question 4

what do 1-way ANOVA’s examine

Answer 4

the differences between 2 or more groups/conditions

Question 5

what is a within-subject experiment

Answer 5

when all subjects do the same condition, repeated measures

Question 6

what is a between-subjects experiment

Answer 6

when not all subjects do the same condition, independent groups

Question 7

are ANOVA’s parametric or non parametric

Answer 7

parametric

Question 8

that is it meant by type 1 error

Answer 8

when there is a false positive

Question 9

what is parametric data

Answer 9

when the data comes from a “normal” sample and appears bell shaped on graphs, normal distribution

Question 10

what is homogeneity variance

Answer 10

its when the average squared distance of score from the mean is the same across all groups sampled in the study

Question 11

what does “factors” refer to in ANOVA’s

Answer 11

the independent variables, there must be at least 2 levels

Question 12

what is the ANOVA conceptual basis

Answer 12

ANOVA’s are used to test whether the difference between means are statistically significant, they also compare the variation explained by the manipulation with variance left unexplained (e.g individual differences would be an unexplained reason there is a variation in scores between subjects)

Question 13

how is the F value calculated

Answer 13

variance explained divided by the variance unexplained

Question 14

why is it good that if our F value is a big number

Answer 14

it suggests there is more explained variance than unexplained variance

Question 15

how does the F value effect the P value

Answer 15

the bigger the F value, the smaller the P value will be as there is less probability that the results consist of external factors interfering

Question 16

what are the two df values that we have to report

Answer 16

the first df value (the smallest one that goes first in a report) stands for the number of factors - 1
the second df value (the larger one that we report after the first one) stands for the number of participants -1

Question 17

what does df stand for and what does it mean

Answer 17

it stands for degrees of freedom and it represents the number of values that are free to vary in a a data set

Question 18

what are the steps to carry out a 1-way between subjects ANOVA on SPSS

Answer 18

you need to make sure you DV and IV’s are in their separate columns, then you need go to analyse –> compare means –> 1-way ANOVA, then select you DV and IV’s

Question 19

how do you report a 1-way ANOVA

Answer 19

F (df (number of IV’s -1), df(number of subjects -1) = F value, P= p value

Question 20

why should Levenes test be non significant on the ANOVA summary table

Answer 20

if it was significant, it would suggest that there is high homogeneity variance, suggesting there may be external factors that have effected the data (needs to be below .005)

Question 21

how do you carry out a 1-way within subjects ANOVA

Answer 21

make sure your DV and IV’s are in separate columns and then go to analyse –> general linear models –>repeated measures and then fill out dialogue boxes

Question 22

what does Mauchly test of sphericity show

Answer 22

it is an extra assumption test, you want this to be non significant

Question 23

what do you do if your Mauchly test is significant

Answer 23

you should consider doing a multivariate test