Discovering Statistics; Chapter 1

Question 1

When are qualitative methods of research used?

Answer 1

When the experimenter needs to analyse language.

Question 2

Briefly outline the research process.

Answer 2

Research question -> generate theory -> generate hypothesis (identify variables) -> collect data to test theory (measure variables) -> analyse data (graph data and fit a model)

Question 3

What are variables?

Answer 3

The ‘things’ in an experiment that change or don’t change which are measured by the experimenter.

Question 4

What is a theory?

Answer 4

An idea or explanation based on observations in a natural setting.

Question 5

What is a hypothesis?

Answer 5

A prediction from a theory.

Question 6

What is falsification?

Answer 6

Act of disproving a hypothesis/theory.

Question 7

What is the independent variable?

Answer 7

A variable where the value is not dependant on other variables.

Question 8

What is the dependant variable?

Answer 8

The variable where the value depends upon the manipulation of the experiment.

Question 9

What is the predictor variable?

Answer 9

A variable though to predict an outcome.

Question 10

What is the outcome variable?

Answer 10

It is a variable which is thought to change as a function of changes in the predictor variables.

Question 11

What are categorical variables?

Answer 11

Categorical variables are entities divided into distinct categories.

Question 12

What are continuous variables?

Answer 12

Where entities get a distinct score.

Question 13

What is measurement error?

Answer 13

The discrepancy between the numbers used to represent what we’re measuring and the actual value of what we’re measuring.

Question 14

What is validity?

Answer 14

The extent to which the measuring instrument measures what it intends to measure.

Depends on reliability.

Question 15

What is reliability?

Answer 15

The extent to which the measuring instrument finds the same results in repetition.

Question 16

What is correlational/cross-sectional research?

Answer 16

Where research a observe what naturally occurs without interference.

Question 17

What is longditudinal research?

Answer 17

Repeatedly measuring the same people over a long period of time.

Question 18

What is ecological validity?

Answer 18

How a studies results can be generalised to the public.

Question 19

What is tertium quid?

Answer 19

A third person or thing interfering with the observation.

Question 20

What are confounding (or extraneous) variables?

Answer 20

Variables from the real world which can influence results (such as time of day)

Question 21

When are quantitative methods of research used?

Answer 21

When numbers are involved in the data.

Question 22

What are between group/independent measures experiments?

Answer 22

Different groups do every condition.

Question 23

What are within subject/repeated measures experiments?

Answer 23

One group does all experimental conditions.

Question 24

What is systematic variation?

Answer 24

The variation that occurs due to the experimenter doing something in one condition, but not the other.

Question 25

What is unsystematic variation?

Answer 25

The variation that results from random factors that exist between experimental conditions (eg. time of day). We aim to keep this variation as small as possible through randomization.

Question 26

What are practice effects?

Answer 26

Performing differently in the second condition due to familiarity. It is overcome with counterbalancing (AB/BA).

Question 27

What are boredom effects?

Answer 27

Performing differently in the second condition due to boredom/tiredness.

Question 28

What is a normal distribution of the data?

Answer 28

Data displayed as a bell-shape curve on the graph.

Question 29

What is a positive skew?

Answer 29

Frequent scores gathered to the left of the graph.

Question 30

What is a negative skew?

Answer 30

Frequent scores gathered to the right of the graph.

Question 31

What is kurtosis?

Answer 31

The ‘pointyness’ of the curve.

Question 32

What is leptokurtis?

Answer 32

Otherwise known as positive kurtosis; a tall curve.

Question 33

What is platykurtis?

Answer 33

Otherwise known as negative kurtosis; a flat curve.

Question 34

What is the central tendency?

Answer 34

The value calculated to assess where the centre of frequency distributions lie.

Question 35

What is the mode?

Answer 35

The score that occurs the most frequently.

Question 36

What is bimodality?

Answer 36

A set of scores that has two scores which are equally as frequent as each other.

Question 37

What is multimodality?

Answer 37

A set of scores that has three or more scores which are equally as frequent as each other.

Question 38

What is the median?

Answer 38

The middle score.

Question 39

What is the mean?

Answer 39

A measure of central tendency. Calculated by the sum of scores being divided by the total number of scores.

Question 40

What is the range?

Answer 40

The largest score - the smallest score.

Question 41

What is the interquartile range?

Answer 41

Range of the middle 50% of scores (upper quartile - lower quartile).

Question 42

What is the lower quartile?

Answer 42

The median of the bottom 50% of scores.

Question 43

What is the upper quartile?

Answer 43

The median of the top 50% of scores.

Question 44

What is the deviance?

Answer 44

The difference between the raw score and the value of the mean.

Question 45

What is the equation for a z-score?

Answer 45

(score - mean) / standard deviation.