oneway anova

Question 1

What are independent variables?

Answer 1

variables that are explicitly manipulated

Question 2

What are dependent variables?

Answer 2

Variables that are our data (ie. FA, HR)

Question 3

What is the population?

Answer 3

All the data we can observe

Question 4

What is Random Sampling?

Answer 4

A subset of the population, hopefully representative of the population as a whole

Question 5

What is Standard Deviation?

Answer 5

A measure of variance

Question 6

How do you calculate the variance?

Answer 6

SD^2

Question 7

What is a Normal Distribution (aka Gaussian Distribution)?

Answer 7

The sum of all variables. Has a mean which falls at the highest peak. The variance determines how spread out a distribution is.

Question 8

What is bimodality?

Answer 8

A distribution that has 2 peaks

Question 9

What does within-groups mean?

Answer 9

Chance variation

Question 10

What does between groups mean?

Answer 10

Chance variation and another effect

Question 11

What is a One-way ANOVA?

Answer 11

A comparison of variation within-groups to variation between groups. Tells us if there is a significant difference among groups but not where that difference is. Produces an F-statistic which produces a p-value.

Question 12

What does a large F-Stat tell us?

Answer 12

There is evidence that the difference is reliable

Question 13

What are the Degrees of Freedom for a One way ANOVA?

Answer 13

2

Question 14

What is an F-Distribution?

Answer 14

Allows us to find the probability of observing an F-Stat with a specific value. The F-Statistic is assessed against the F-Distribution

Question 15

Why do we need Post Hoc Tests?

Answer 15

• the t-test is probably not enough

- require multiple comparisons

Question 16

What is the Bonferroni test?

Answer 16

It automatically adjusts the p-value to correct for the number of comparisons. Creates a more conservative false alarm rate.

Question 17

What is Apophenia?

Answer 17

The experience of seeing meaningful patterns in random or meaningless data

Question 18

Because of the central limit theorem, many of the variables that we study in psychology are normally distributed. What best describes the normal distribution?

Answer 18

A distribution which has its mode at some value and decreases as you move away from that value in both directions

Question 19

Which 2 parameters describe the normal distribution?

Answer 19

Mean & Variance

Question 20

What does the p-value tell us in a one-way ANOVA?

Answer 20

The p-value tells us the probability of observing our sample of data given that the null hypothesis of no difference between groups is true

Question 21

If there is a systematic effect of our manipulation on the observed data then:

Answer 21

• The between groups variation will be larger than the within-groups variation
• The F-ratio will be sufficiently large
• The means of our conditions will be different

Question 22

What is one reason why you might conduct post-hoc analyses after running an ANOVA?

Answer 22

The ANOVA tells that there is an effect but not where the effect is (ie. between which groups) or the size of the effect