se notation

Question 1

population

Answer 1

the whole set of items that are of interest

Question 2

census

Answer 2

observers or measures every member of a population

Question 3

a sample

Answer 3

is a selection of observations taken from a subset of the population which is used to find out information about the population

Question 4

indiuviual units of a population are know as what

Answer 4

sampling units

Question 5

spampling frame

Answer 5

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

Question 6

a simple random sample

Answer 6

size n is one where every sample size n has an equal chance of being selected

Question 7

systematic sampling

Answer 7

the required element are chosen at regular intervals from an ordered lists

Question 8

quota sampling

Answer 8

an interviewer or researcher selects a sample that reflects the characterises of the whole population

Question 9

stratified sampling

Answer 9

the population is divided into mutually exclusive strata and a random sample is taken from each

Question 10

number sampled in a stratum formula

Answer 10

number in stratum divided by population x overall sample size

Question 11

advantage of census

Answer 11

it should give a completely accurate result

Question 12

disadvantage of census

Answer 12

time consuming and expensive
cannot be used when the testing process destroys the item
hard to process large quantity of data

Question 13

advantage of sample

Answer 13

fewer people have top respond
less data to process than in a census
less time conbsuyming and expensive than a census

Question 14

disadvantage of sample

Answer 14

the data may not be accurate

may not be large enough to give info about small sub groups of population

Question 15

advantage of simple random sampling

Answer 15

free of bias
easy and cheap to implement for small population and small samples
each sampling unit has a known and equal chance of selection

Question 16

disadvantage

Answer 16

not suitable when population size or the sample size is large as it its potentially time consuming, disruptive and expensive
a sampling frame is needed

Question 17

systemic sampling advantage

Answer 17

simple and quick to use

suitable for large samples and large populations

Question 18

systemic sampling disadvantage

Answer 18

a sampling frame needed

it can introduce bias if the sampling frame is not random

Question 19

stratified sampling advantage

Answer 19

sample accuracy reflects the population structure

grates proptionasl representation of groups within population

Question 20

stratified sampling disadvantage

Answer 20

population must be creamy classified into distinct strata

selection within each stratum suffers from the same disadvantage as simple random sampling

Question 21

quota sampling advantage

Answer 21

allows a small sample to still be repressive go the population
no sampling frame needed
quick easy and inexpensive
allows for easy comparison between different groups within a population

Question 22

quota sampling disadvantage

Answer 22

non random sampling can introduce bias
population must be divided into groups which can be costly or inaccurate
increasing scope of study increases number of groups which adds time and expense
non responses are not recorded as such

Question 23

opportunity sampling advantage

Answer 23

easy to carry out

inexpensive

Question 24

opportunity sampling disadvantage

Answer 24

unlikely to provide a representative sampling

high;y dependent on indivuial researcher