Applied

Question 1

Definition of population

Answer 1

The whole set of items that are of interest

Question 2

Definition of sample

Answer 2

Some subset of the population intended to represent the population

Question 3

Definition of sampling frame

Answer 3

List of sampling units from the population from which a sample is drawn

Question 4

Name three random ways to sample

Answer 4

Simple random, systematic, stratified

Question 5

Name two non-random ways to sample

Answer 5

Quota, opportunity

Question 6

What is simple random sampling?

Name some + and -

Answer 6

In the sampling frame each item is numbered. Random numbers are generated until the sample is taken.

+ Unbiased
+ Fair

• No consent
• Unrepresentative
• Could end up with an unrealistic sample
• Requires a sampling frame

Question 7

What is systematic sampling?

Name some + and -

Answer 7

The required elements are taken at regular intervals starting from a random number in the first interval

+ Simple
+ Quick and inexpensive
+ Suitable for large samples

• Can introduce bias if sampling frame is not random
• Sampling frame required

Question 8

What is stratified sampling?

Names some + and -

Answer 8

The population is divided into strata and a simple random sample is taken from each group

+ Reflects population structure
+ Proportional representation of groups

• Strata have to be relavant and distinct
• Sampling frame required
• Consent is required
• could end up with an unrealistic sample within the strata

Question 9

What is quota sampling?

Name some + and -

Answer 9

Populations are divided into strata and a quota is set for each of the strata from which volunteers are taken to fill the numbers

+ Proportional representation
+ No sampling frame needed
+ Quick easy and inexpensive
+ Allows for easy comparison

• Could be biased
• Strata must be relavant and distinct
• Increasing scope makes it difficult
• Non-responses are not recorded

Question 10

What is opportunity sampling?

Name some + and -

Answer 10

Sample taken from available people who fit the criteria

+ Inexpensive
+ Safety and consent
+ Easy to carry out

• Likely to be unrepresentative
• Highly dependent on the individual researcher
• Propaganda or news needs to be available for everyone

Question 11

What is numerical data called?

Answer 11

Quantitative

Question 12

What are the two types of numerical data called?

Answer 12

Discrete (only certain values)

Continuous (can have any decimal value)

Question 13

What is non-numerical data called?

Answer 13

Qualitative

Question 14

Large data set stuff:

Answer 14

1987 + 2015
8 weather stations
Heathrow- England but hot and windy
Leucars - Windy
3 other England 
Jacksonville, USA - Hot
Beijing, China - Hottest, still
Perth, Australia - Similar temp to UK, Very rainy

Question 15

Typical values of gust

Answer 15

(UK only) 8-52mm

Question 16

Typical values of rainfall

Answer 16

(UK) 0-66mm

Question 17

Typical values of Pressure

Answer 17

988-1038hPa

Question 18

Typical values of wind speed on Beaufort scale

Answer 18

Max- fresh - 5

Question 19

Typical values of Sunshine

Answer 19

(UK only) 0-16hrs

Question 20

Typical values of cloud cover

Answer 20

0-8 ocktas

Question 21

Name the measures of location

Answer 21

Maximum
Minimum
Quartiles
Percentiles
Deciles 

Measures of central tendency:
Mode
Median
Mean

Question 22

Name the measures of spread

Answer 22

Range
Standard deviation
Varience
Interquartile range

Question 23

Interpolation formula

Answer 23

LB + (pig/ gf x cw)

Question 24

Variance equation

Answer 24

Variance = sum of x^2/ number - (mean of x)^2

Variance= standard deviation^2

Question 25

Outliers

Answer 25

2 Standard deviations from the mean

UQ + 1.5xIQR
LQ - 1.5xIQR