Unit 2: Organization of Data and Statistical Analysis

Question 1

what are sampling techniques?

Answer 1

methods used to select a group from a population you wish to study

Question 2

what is a population?

Answer 2

all individuals of items being studied

Question 3

what is a sample?

Answer 3

a group of people or items that are selected from the population to study

Question 4

what is a sampling frame?

Answer 4

members of a population that actually have a chance of being selected for a study

Question 5

what is statistical bias?

Answer 5

systematic error in a survey or sampling method which favours certain outcomes

Question 6

what are types of qualitative and quantitive datas?

Answer 6

qualitative: nominal and ordinal
quantitive: discrete and continuous

Question 7

what is nominal data?

Answer 7

data that can be put into categories without any logical order (ex. colour)

Question 8

what is ordinal data?

Answer 8

data that can be put into categories with logical order (ex. customer satisfaction)

Question 9

what is discrete data?

Answer 9

data that can be counted or expressed as integers (ex. # of children)

Question 10

what is continuous data?

Answer 10

data that can be measured and expressed as any rational number (ex. height)

Question 11

how do you display nominal data?

Answer 11

bar charts, pie chart, or frequency table

Question 12

how do you display ordinal data?

Answer 12

ordered bar chart, line graphs

Question 13

how do you display discrete data?

Answer 13

horizontal (or vertical) bar chart, stacked bar chart

Question 14

what data is good for box plots?

Answer 14

discrete or continuous

Question 15

what graph is continuous data most frequently shown on?

Answer 15

scatter plot or histogram

Question 16

what are random and non-random sampling techniques (random)?

Answer 16

random - give all members of the population an equal chance of being selected for the sample
non random - techniques are more likely to be biased and may skew data

Question 17

what is the simple random technique (random)?

Answer 17

randomly selects individual/items for sample and must ignore defining characteristics

Question 18

what is the systematic sampling technique (random)?

Answer 18

puts the population into an ordered list and selects sample using regular intervals (ex. every other person)

Question 19

what is the stratified sampling technique (random)?

Answer 19

divides population into groups and selects sample in same proportion to the group

Question 20

what is the cluster technique (random)?

Answer 20

divides the population into groups and randomly selects groups for the sample

Question 21

what is the multi-stage sampling technique (random)?

Answer 21

divide population into a hierarchy with different levels and choose a random sample at each level

Question 22

what is the convenience sample technique(non-random)?

Answer 22

sample selected because it is easily accessible and was the fastest method of data collection

Question 23

what is the judgment sampling technique(non-random)?

Answer 23

researcher hand-select individuals/items based on specific criteria which may ignore certain characteristics of the population intentionally

Question 24

what is the voluntary sampling technique (non-random)?

Answer 24

participation at discretion of the respondent and typically has emotional responses

Question 25

what is bias?

Answer 25

it occurs when characteristics of the sample don't reflect the population and comes from the sampling method or from the survey

Question 26

what is sampling bias?

Answer 26

the selected sample doesn't represent the characteristics of the population and a non-random sampling method is used

Question 27

what is measurement bias?

Answer 27

data collection method consistently over or under estimates a characteristic of the population

Question 28

what is leading question bias?

Answer 28

form of measurement bias that prompts for a particular response

Question 29

what is loaded question bias?

Answer 29

form of measurement bias where questions contain information or wording to influence a response

Question 30

what is response bias?

Answer 30

false or misleading answers which may have people uncertain on how to respond

Question 31

what is non-response bias?

Answer 31

groups may be under represented because members of the group choose not to participate

Question 32

what is measures of spread?

Answer 32

indicates how closely a set of data clusters around its center

Question 33

what is the range?

Answer 33

a calculation of the difference between the highest and lowest values in a data set

Question 34

what are percentiles?

Answer 34

the percent of all data in a set that are less than or equal to a specific data value

Question 35

what is standard deviation?

Answer 35

the square root of the mean of the squares of the deviations

Question 36

what is variance?

Answer 36

the mean of the squares of the deviations. this is the square of the standard deviation

Question 37

what are z-scores?

Answer 37

a measure of how many standard deviations a particular data value is from the mean

Question 38

what is interpolation?

Answer 38

when you estimate between known data values

Question 39

what is extrapolation?

Answer 39

when you predict beyond the range of data

Question 40

what is non-linear regression?

Answer 40

an analytic technique for finding the curve of best fit for data

Question 41

what is an outlier?

Answer 41

a point that doesn't follow the trend of the data

Question 42

what is a hidden variable?

Answer 42

a variable that affects or obscures the relationship of 2 variables that can result in a false correlation of fragmented trend

Question 43

what is a residual?

Answer 43

the vertical distance between a data point's actual (observed) dependent value and the value predicted by the line of best fit model

Question 44

correlation vs causality

Answer 44

strong positive correlations don't always show cause and effect

Question 45

what is the causal relationship direct cause and effect?

Answer 45

a change in the independent variable directly causes a change in the dependent variable (x causes y)

Question 46

what is the causal relationship common cause?

Answer 46

an external (third) variable causes 2 variables to change (z causes x and y)

Question 47

what is the causal relationship reverse cause and effect?

Answer 47

the independent and dependent variables are reversed in the process of establishing causality (y causes x)

Question 48

what is the causal relationship accidental relationship?

Answer 48

a correlation exists without any casual relationship between variables

Question 49

what is the causal relationship presumed relationship?

Answer 49

a relationship that makes sense, but no cause and effect or common cause is apparent