science practices 0.6

Question 1

quantitative data

Answer 1

numbers. not up for interpretation

Question 2

qualitative data

Answer 2

used to deal with descriptive data

— more investigative and open ended

Question 3

descriptive statistics, the 3 measures

Answer 3

numerical data used to measure and describe characteristics of groups.
- mean, median, mode

Question 4

mean

Answer 4

arithmetic average. add scores then divide by number of scores

Question 5

median

Answer 5

middle score in a rank-ordered distribution

Question 6

mode

Answer 6

most frequently occurring score

Question 7

normal curve distribution

Answer 7

symmetrical curve. most scores fall to the mean

Question 8

skewed distribution

Answer 8

representation of scores that lack symmetry around the avg.

Question 9

bimodal distrbution

Answer 9

2 distinct peaks, indicating 2 different values / groups with the highest frequency

• two different modes

Question 10

percentile rank

Answer 10

the percentage of scores that are less than a given score

Question 11

range

Answer 11

The difference between the highest and lowest scores in a distribution

Question 12

standard deviation

Answer 12

Indicates the average distance from the mean –a computed measure of how much scores vary around the mean

Question 13

inferential statistics

Answer 13

numerical data that allows researchers to generalise. infer the probability of something being true of a population.

• Can I generalise and predict or is it a fluke?

Question 14

When is an observed difference reliable (not a fluke)?

Answer 14

• representative sample
• low standard deviation
• bigger sample

Question 15

making inferences – when is a difference significant (not just by chance)?

Answer 15

• When sample averages are reliable and the difference between them is relatively large (statistically significant)
• p value less than 0.05 (less than 5% chance that results are due to chance)

Question 16

Statistical significance (p-value)

Answer 16

the likelihood that a relationship between two or more variables is caused by something and not just by chance or luck.

Question 17

null hypothesis

Answer 17

no predicted difference between groups

• rejected if p value is less than 0.05

Question 18

effect size

Answer 18

The strength of a relationship between two variables.

• larger the effect size, the more one variable can be explained by the other.
• how meaningful results are in the real world