populations and samples

Question 1

population

Answer 1

the whole set of items that are of interest

Question 2

census

Answer 2

observes of measures every member of a population

Question 3

sample

Answer 3

a selection of observations taken from a subset of the population to find out information about the population as a whole

Question 4

advantages of a census x1

Answer 4

should get a completely accurate result

Question 5

disadvantages of a census x4

Answer 5

time consuming
expensive
difficult to process all the data
cants be used when testing items as it destroys them

Question 6

advantages of a sample x4

Answer 6

less time consuming
cheaper
requires fewer items
easier to process data due to fewer items

Question 7

disadvantages of a sample

Answer 7

data may not be as accurate

sample may not be large enough to give information about small sub-groups of the population

Question 8

sampling units

Answer 8

individual units of a population

Question 9

sampling frame

Answer 9

sampling units of a population which are individually named or numbered to form a list

Question 10

how can different samples lead to different conclusions?

Answer 10

natural variation in a population

Question 11

how can you make a sample more accurate?

Answer 11

by using a larger sample

Question 12

when would you need a larger sample?

Answer 12

if the population is very varied