Stats

Question 1

What is nominal data?

Answer 1

Data that is categorical e.g. gender, colour

Question 2

What is ordinal data?

Answer 2

Data that has a natural order e.g. position in a race

Question 3

What is continuous data?

Answer 3

Data that is on a scale where differences between intervals are always the same e.g. height

Question 4

What is the independent variable?

Answer 4

Variable manipulated by the experimenter - the one you use to test effects on the dependent variable

Question 5

What is the dependent variable?

Answer 5

Variable that you measure

Dependent on the independent variable

Question 6

What is the confounding variable?

Answer 6

Variable that has an effect on the dependent variable but that you are not interested in testing.

Question 7

What is a between subjects design?

Answer 7

Independent samples where each subject is presented in a different condition

Question 8

What is a within subjects design?

Answer 8

Related samples where each participant receives all conditions

Question 9

What is inter-observer reliability?

Answer 9

Do 2 people get the same result when examining the sample?

Question 10

What is intra-observer reliability?

Answer 10

Does one person get the same result when examining the sample at different times?

Question 11

From basic tests how do you work out if the data is normally distributed?

Answer 11

Do a mean, median and mode test.

If all values are relatively similar data is normally distributed.

Question 12

What tests determine whether data is normally distributed?

Answer 12

Kolmogorov-Smirmoff Test

Shapiro-Wilk Test

Question 13

What tests do you use to test the means of two sets of data for differences?

Answer 13

Two independent sample t-test

Two paired smaple t-test

Question 14

What test do you use to test the variance of two sets of data?

Answer 14

One sample t-test

Question 15

What test do you use to test the means of more than two sets of data for differences?

Answer 15

One way ANOVA

Two way ANOVA

Question 16

What do the terms one sided/two sided (tailed) mean when describing hypotheses?

Answer 16

One tailed - can be answered with yes or no e.g. “a happy dog will eat more” - tells you what type of effect there will be
Two tailed - can be answered with different outcomes e.g. “mood affects the appetite of dogs” - tells you there will be an effect

Question 17

What is a type 1 error?

Answer 17

Rejecting the null hypothesis when it is true

aka diagnosing a male as pregnant

Question 18

What is a type 2 error?

Answer 18

Failing to reject the null hypothesis when it is false

aka telling a pregnant lady she is not pregnant

Question 19

If your data was non-parametric what test would you do instead of an independent samples t-test?

Answer 19

Mann-Whitney U test

Question 20

If your data was non-parametric what test would you do instead of a paired samples t-test?

Answer 20

Wilcoxon Signed-rank test

Question 21

What does it mean if a study is under-powered?

Answer 21

Too little data collected so nothing looks statistically significant

Question 22

What does it mean if a study is over-powered?

Answer 22

Too much data collected so everything looks statistically significant

Question 23

What two forms do you need to give the participants of your study?

Answer 23

Ethics consent form

Participant information sheet

Question 24

How do u calculate the mean?

Answer 24

Add all numbers divide by sample size

Question 25

How do u calculate mode?

Answer 25

Most common number

Question 26

How do u calculate median?

Answer 26

Middle number

Question 27

How do u calculate standard deviation?

Answer 27

Work out the Mean (the simple average of the numbers)
Then for each number: subtract the Mean and square the result.
Then work out the mean of those squared differences.
Take the square root of that and we are done!

Question 28

What does standard deviation show?

Answer 28

How spread out the data is from the mean
High SD = very spread out
Low SD = little spread