Section 1 (Pgs 1-20)

Question 1

What are descriptive statistics?

Answer 1

Summary statistics that describe features of the data

Question 2

What is inference?

Answer 2

The act of drawing a conclusion about a population based on a sample

Question 3

What is data?

Answer 3

The raw material for data analysis

Question 4

What are the 2 main types of data?

Answer 4

Quantitative

Qualitative

Question 5

What is another name for qualitative data?

Answer 5

Categorical

Question 6

what are the types of quantitative data?

Answer 6

Discrete

Continuous

Question 7

Describe discrete data?

Answer 7

Whole numbers e.g. counts

Question 8

Describe continuous data?

Answer 8

Continuous measurement can take any value, depending on the accuracy of the recording instrument e.g. height

Question 9

What is qualitative data?

Answer 9

Data where individuals or objects are classified into groups e.g. obese, overweight, normal weight, underweight or different types of diets

Question 10

What are the types of qualitative data?

Answer 10

Ordinal
Nominal
Binary (binomial)

Question 11

What type of qualitative data has a relationship between the categories meaning they can be ordered?

Answer 11

Ordinal

Question 12

What type of qualitative data has no relationship between the categories?

Answer 12

Nominal

Question 13

Name of the ordinal scale representing the degree of agreement with a statement?

Answer 13

Lickert scale

Question 14

What type of qualitative data is categorial with only 2 values?

Answer 14

Binary/ binomial

Question 15

What type of data is eye colour?

Answer 15

Nominal

Question 16

What type of data is severity of disease?

Answer 16

Ordinal

Question 17

What type of data is number of alcohol units?

Answer 17

Discrete

Question 18

What type of data is waist to hip ratio?

Answer 18

Continuous

Question 19

What type of data is time in hospital?

Answer 19

Discrete

Question 20

What type of data is mortality?

Answer 20

Binary

Question 21

What is the normal structure of a table?

Answer 21

Row per case

Column per variable

Question 22

What is it called when a variable is recorded several times e.g. at multiple clinic visits, often represented by multiple columns on a table?

Answer 22

Repeated variables

Question 23

What should you always do to data before beginning a formal analysis?

Answer 23

Inspect it

Question 24

What is a population?

Answer 24

All the members of the particular group under study

Question 25

What 2 properties should a sample have?

Answer 25

Large enough to detect any differences that are of interest | Representative of the population

Question 26

What do we have to be careful that a sample for a research study is not?

Answer 26

Biased

Question 27

What are the 2 most common ways to prevent biased?

Answer 27

Random sampling | Stratified random sampling

Question 28

What is a random sample?

Answer 28

One in which each member of the population has an equally likely, non-zero chance of being included

Question 29

When is a stratified sample taken?

Answer 29

When there are categories in the population that must be represented

Question 30

What non-ideal method of sampling is often done?

Answer 30

Convenience sampling

Question 31

What is convenience sampling?

Answer 31

Sample is not chosen randomly but is all that is available e.g. those that present at a clinic

Question 32

When using convenience sampling, what must be done?

Answer 32

Collection of full information to investigate for possible bias at the analysis stage

Question 33

Sampling method used for a diabetiologist's research study of the long term effects of T2DM in his patients?

Answer 33

Convenience sample

Question 34

Sampling method used for a government investigation into the proportion of children born with CP in the last year (no central register)?

Answer 34

Random sample

Question 35

Types of sampling method?

Answer 35

Random Stratified Convenience

Question 36

What are the 7 main ways of presenting data?

Answer 36

``` Tables Bar charts Pie charts Histograms Stem and leaf plots Box and whisker plots Scatter plots ```

Question 37

What 2 ways are used to present qualitative data?

Answer 37

``` Bar charts (can also be used to represent discrete data) Pie charts ```

Question 38

What 4 ways are used to present quantitative (usually continuous) data?

Answer 38

Histograms Stem and leaf plots Box and whisker plots Scatter plots

Question 39

What do scatter plots do?

Answer 39

Display the relationship between 2, usually continuous, variables

Question 40

What is the purpose of organising data into tables?

Answer 40

Helps to identify errors, trends and special cases

Question 41

What type of table are categorical variables often summarised in?

Answer 41

A contingency table

Question 42

What does a contingency table do?

Answer 42

Gives the number or percentage in each category (if giving percentage, must also give the count and the denominator as a percentage with no other information can be misleading)

Question 43

If making a 3D pie chart, what should the volume represent?

Answer 43

The proportion

Question 44

What is the frequency distribution function?

Answer 44

The relationship between the data values and their frequencies

Question 45

How to calculate the relative frequency?

Answer 45

Subgroup count divided by total count

Question 46

What does the height of each column of a histogram represent?

Answer 46

Frequency

Question 47

What does the wide of a column on a histogram represent?

Answer 47

Grouping interval

Question 48

What is the areas of the columns of a histogram proportional to?

Answer 48

The frequencies in each group

Question 49

What is a relative frequency histogram?

Answer 49

One in which the height of the column is labelled with the relative frequency

Question 50

What is the total area of columns in a relative frequency histogram? Why?

Answer 50

1 Corresponds to the probability of a subject chosen at random having a height in any of the classes. This is a certainty -> probability therefore = 1

Question 51

How is a frequency polygon constructed?

Answer 51

By joining the midpoints at the top of each column of the histograms

Question 52

What does the probability density function provide information about?

Answer 52

Probability of each variable

Question 53

How is a probability density function represented graphically?

Answer 53

By a frequency polygon in which the vertical axis corresponds to relative frequency

Question 54

What are the advantages of a stem and leaf diagram over a histogram? (2)

Answer 54

It is easier to construct | The individual values of the data are shown

Question 55

What do the whiskers on a box and whisker plot represent?

Answer 55

The minimum and maximum value (together form the range)

Question 56

How much of the data does the box in a box and whisker plot contain?

Answer 56

50%

Question 57

What does the upper and lower whiskers of a box and whisker plot sometimes represent?

Answer 57

The values above/below which 2.5% of values lie

Question 58

What does a box-and-whisker plot provide information about?

Answer 58

The symmetry and variability fo the distribution of the data

Question 59

What can be calculated form a scatter plot to assess the strength of the linear relationship?

Answer 59

Coefficient of correlation

Question 60

What is the name of the line on a scatter plot?

Answer 60

Regression line