Workbook 1- LDS And Sampling

Question 1

Population

Answer 1

Set of things that you are interested in. For example all the people in the UK

Question 2

Census

Answer 2

Observes or measures every member of the population eg asking everyone their height

Question 3

Parameter

Answer 3

A number that describes the entire population such as mean or standard deviation of the population eg mean height

Question 4

Sample

Answer 4

Subset of the population, this is used to find info about the population as a whole eg measuring 200 people out of 2000

Question 5

Statistic

Answer 5

A value calculated from a sample such as the mean of a sample. Can be used to estimate the parameter eg mean of a sample is the mean of the population

Question 6

Sampling Unit

Answer 6

An individual unit from the population eg a person living in the UK

Question 7

Sampling Frame

Answer 7

A list of all sampling units in the population eg the electoral register

Question 9

Simple Random Sampling

Answer 9

-Number all the items in the population
-Use random numbers to select sample

Question 10

Systematic Sampling

Answer 10

• Number all items in the population
• n= population size / sample size
• use random numbers from 1 to n to select the first item
• choose every nth item after that

Question 11

Stratified Sampling

Answer 11

• the population will be divided into groups
• decide how many to sample from each group using: (number in group / number in population) x sample size

Question 12

Non Random Sampling Methods

Answer 12

Used when no sampling frame availiable

Question 13

Opportunity Sampling

Answer 13

Your sample consists of any items which are availiable to be sampled

Question 14

Quota Sampling

Answer 14

-The population is divided into groups. The same proportion of items from each group are included in the sample
-Opportunity sampling is used to sample items until the required number from each group has been sampled

Question 15

Large Data Set Time Periods

Answer 15

May-October 1987
May-October 2015

Question 16

5 UK Weather Stations

Answer 16

Camborne
Heathrow
Hurn
Leeming
Leuchars

Question 17

3 Oversea Weather Stations

Answer 17

Beijing
Jacksonville
Perth

Question 18

11 Variables, their Units and approx mean values

Answer 18

Daily Mean Temp- ‘c- 12’c
Daily Total Rainfall- mm- 4mm
Daily Total Sunshine- hours- 15
Daily Max Relative Humidity- %- 80
Daily Mean Windspeed- knots- 10
Daily Max Gust- knots- 14
Daily Max Wind Direction- degrees
Daily Max Gust Direction- degrees
Cloud Cover- oktas- 4.2
Visibility- decametres (dam)
Pressure- hectorpascals (1hPa=100Pa)

Question 19

Which variables are collected for overseas weather stations

Answer 19

Daily Max Temp
Daily Total Rainfall
Daily Mean Windspeed
Pressure