CHAPTER 1

Question 1

what is quantitative data?

Answer 1

• numerical observations or measurements
• can be continuous or discrete

Question 2

what is qualitative data?

Answer 2

• non- numerical observations

Question 3

what is continuous data?

Answer 3

• can take any value on a continuous numerical scale, e.g. height

Question 4

what is discrete data?

Answer 4

• can only take particular values on a continuous numerical scale

Question 5

what is categorical data?

Answer 5

• data that can non- overlapping categories

Question 6

what is ordinal data?

Answer 6

• data which can be written in order and given a numerical rating scale

Question 7

what is bivariate data?

Answer 7

• involves pairs of related data

Question 8

what is multivariate data?

Answer 8

• involves sets of three or more related data values

Question 9

what is primary data?

Answer 9

• data collected firsthand

Question 10

what is secondary data?

Answer 10

• data which someone else has collected

Question 11

what is a population?

Answer 11

• everything or everybody that could possibly be involved in an investigation

Question 12

what is a census?

Answer 12

• a survey or investigation with data taken from every member of a population

Question 13

when is a sample biased?

Answer 13

• when it is not representative of the entire population
• a sample which is collected unfairly or is too small can count as bias

Question 14

what is the sampling unit?

Answer 14

• the people or items that are going to be sampled

Question 15

what is the sampling frame?

Answer 15

• a list of all the sampling units

Question 16

what is the Peterson capture- re capture formula?

Answer 16

N= Mn/m
- N= population
- M= members of population
- n= sample size
- m= number marked

Question 17

what assumptions are made in the Peterson capture- recapture formula?

Answer 17

• the population has not changed (no births or deaths)
• the probability of being caught is equal for all of the individuals
• marks or tags are not lost/ washed off and are always recognisable
• the sample size is large enough to be representative of the population

Question 18

what is a random sample?

Answer 18

• everyone in the population has an equal chance of being chosen
• unbiased and representative of the entire population

Question 19

what is judgement sampling?

Answer 19

• using you judgement to select a sample which is representative of the population

Question 20

what is opportunity sampling?

Answer 20

• using the people or objects which are available at the time to conduct a sample

Question 21

what is cluster sampling?

Answer 21

• when the data naturally splits into groups. e.g. geographical areas
• the list of clusters is the sampling frame, some clusters are randomly selected from it to make the sample

Question 22

what is systematic sampling?

Answer 22

• take a starting point from the sampling frame at random, then choose items at regular intervals
• for example, every 10th person on a list

Question 23

what is quota sampling?

Answer 23

• group the population by characteristics such as age/ gender and interview a quota number from each group e.g. 10 males over 25, 15 females aged 35-60

Question 24

what is a stratified sample?

Answer 24

• contains members of each stratum in proportion to the size of that stratum, the sample from each stratum is selected randomly

Question 25

stratified sample equation?

Answer 25

(amount of students in stratum/ total population) x sample size

Question 26

what does repeating an experiment and coming out wit the same result show you?

Answer 26

• the data is likely to be valid and reliable

Question 27

what is a questionnaire?

Answer 27

• a set of questions designed to obtain data

Question 28

what is the person completing a questionnaire called?

Answer 28

• the respondent

Question 29

what is an open question?

Answer 29

• has no suggested answers

Question 30

what is a closed question?

Answer 30

• has a set of given answers to chose from

Question 31

issues with an open question?

Answer 31

• every respondent could give a different answer, so it can be difficult to summarise and analyse the answers

Question 32

what to include in questionnaires?

Answer 32

• questions with short and simple language
• avoid biased questions
• ensure intervals do not overlap
• ensure it includes all possible answers
• include time frame
• avoid questions which respondents are unlikely to answer honestly

Question 33

what is a pilot survey?

Answer 33

• a survey conducted on a small sample to test the design, method and reliability of that survey

Question 34

what is an outlier or anomalous data value?

Answer 34

• value which does not fit the pattern of the data
• you can ignore the outlier if it is due to a measuring or recording error

Question 35

what is a random response method?

Answer 35

• uses a random event to decide how to answer the question

Question 36

what is cleaning data?

Answer 36

• identifying and either correcting or removing inaccurate data values (caused by recording or other errors) or extreme values
• removing units or other symbols from data
• deciding what to do about missing data

Question 37

what is an extraneous variable?

Answer 37

• variables which you are not interested in but could affect the result of your experiment

Question 38

what is a control group?

Answer 38

• tests the effectiveness of a treatment
• use random selection to select two groups of people
• give the test group the treatment and the control group no treatment
• compare the results of the two groups to see how effective the treatment is

Question 39

what is a matched pair test?

Answer 39

• where two groups of people are used to test the effects of a particular factor
• 2 individuals with everything in common are paired up, except the thing being tested

Question 40

what is a hypothesis?

Answer 40

• an idea that can be tested by collecting and analysing data