Discovering Statistics

Question 1

Sampling variation

Answer 1

Samples will vary because they contain different members of the population

Question 2

Sampling distribution

Answer 2

Frequency distribution of sample means from the same population.

Question 3

Standard error (SE)

Answer 3

Standard deviation of sample means. Usually estimated through statistical procedures rather than collecting many different samples. Measure of how representative sample is likely to be of the population.

Question 4

Confidence intervals

Answer 4

Boundaries within which we believe the true value of the population mean will fall.

Question 5

Systematic variation

Answer 5

Result of some genuine effect (whether it be natural variation between sets of variables or researcher effects). Can be explained by the model we’re using

Question 6

Unsystematic variation

Answer 6

Variation not due to the effect we are studying. Variation that can’t be explained by the model we’re using.

Question 7

One-tailed test

Answer 7

Using a directional hypothesis (x will increase y)

Question 8

Two-tailed test

Answer 8

Non-directional hypothesis (x will increase OR decrease y).

Question 9

Systematic variation

Answer 9

Result of some genuine effect (whether it be natural variation between sets of variables or researcher effects). Can be explained by the model we’re using

Question 10

Unsystematic variation

Answer 10

Variation not due to the effect we are studying. Variation that can’t be explained by the model we’re using.

Question 11

One-tailed test

Answer 11

Using a directional hypothesis (x will increase y)

Question 12

Two-tailed test

Answer 12

Non-directional hypothesis (x will increase OR decrease y).

Question 13

Small effect size correlation coefficient

Answer 13

.10 effect explains 1% of total variance

Question 14

Medium effect size correlation coefficient

Answer 14

.30 effect accounts for 9% of total variance

Question 15

Large effect size correlation coefficient

Answer 15

.50 effect accounts for 25% of variance

Question 16

Small effect size correlation coefficient

Answer 16

.10 effect explains 1% of total variance

Question 17

Medium effect size correlation coefficient

Answer 17

.30 effect accounts for 9% of total variance

Question 18

Large effect size correlation coefficient

Answer 18

.50 effect accounts for 25% of variance

Question 19

Small effect size correlation coefficient

Answer 19

.10 effect explains 1% of total variance

Question 20

Medium effect size correlation coefficient

Answer 20

.30 effect accounts for 9% of total variance

Question 21

Large effect size correlation coefficient

Answer 21

.50 effect accounts for 25% of variance

Question 22

Small effect size correlation coefficient

Answer 22

.10 effect explains 1% of total variance

Question 23

Medium effect size correlation coefficient

Answer 23

.30 effect accounts for 9% of total variance

Question 24

Large effect size correlation coefficient

Answer 24

.50 effect accounts for 25% of variance

Question 25

Small effect size correlation coefficient

Answer 25

.10 effect explains 1% of total variance

Question 26

Medium effect size correlation coefficient

Answer 26

.30 effect accounts for 9% of total variance

Question 27

Large effect size correlation coefficient

Answer 27

.50 effect accounts for 25% of variance

Question 28

Small effect size correlation coefficient

Answer 28

.10 effect explains 1% of total variance

Question 29

Medium effect size correlation coefficient

Answer 29

.30 effect accounts for 9% of total variance

Question 30

Large effect size correlation coefficient

Answer 30

.50 effect accounts for 25% of variance