Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

maths statistics year 1 > 1. data collection > Flashcards

1. data collection Flashcards

(59 cards)

Start Studying
1
Q

census def

A

measures every member of a population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

sample def

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

census advantaged

A

completely accurate results

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sample advantaged

A
  • less time consuming and expensive than census
  • fewer people have to respond
  • less data to process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

census disadvantages

A

-time consuming and expensive
- cannot be used when testing process that destroys items
- hard to process large quantity of data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

sample disadvantages

A
  • data may not be as accurate
  • sample may not be large enough to accurately represent population
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

sampling units

A

individual units of population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

sampling frame

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

three methods of random sampling

A

simple random sampling
systematic sampling
stratified sampling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

simple random sample of size n is when

A

ever sample size of n has equal chance of being selected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

in systematic sampling the required elements are chosen

A

at regular intervals from an ordered list

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

in stratified sampling

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

number of sampled in a stratum=

A

number in stratum/number in population x overall Sample size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

simple random sampling advantages

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

disadvantages of simple random sampling

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

systematic sampling advantages

A

simple and quick to use
suitable for large samples and large populations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

systematic sampling disadvantages

A

sampling frame is needed
it can introduce bias if the sampling frame is not random

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

stratified sampling advantages

A

sample accurately reflects the population structure
guarantees proportional representation of groups within a population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

stratified sampling disadvantages

A

population must be clearly classified into distinct strata
selection within each stratum suffers from the same disadvantages as simple random sampling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

two types of non random sampling

A

quota sampling
opportunity sampling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

in quota sampling

A

researcher selects a sample that reflects the characteristics of the whole population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

in opportunity sampling

A

consists of taking samples from people who are available at the time of the study is carried out and who fit the criteria you are looking for

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

quota sampling advantages

A

allows a small sample to still be representative of the population
no sampling frame required
quick and easy and inexpensive
allows for easy comparison between different groups within the population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

quota sampling disadvantages

Study These Flashcards
A

non random sampling can introduce bias
populations can be divided into groups which can be costly and inaccurate
increase number of group adds more time and expense
non response is not recorded as such

25
opportunity sampling advantages
easy to carry out inexpensive
26
disadvantages of opportunity sampling
unlikely to provide a representative sample highly dependent on individual researcher
27
quantitive data/ variables def
variables or data associated with numerical observations
28
qualitative data/variables def
variables or data associated with non numerical observations
29
continuous variable def
a variable that can take any value in a given range
30
discrete variable def
a variable that can take only specific values in a given range
31
class boundaries tell you
the maximum and minimum values that belong in each class
32
midpoint is
the average of the class boundaries
33
class width is the
difference between the upper and lower class boundaries
34
daily mean temp def
this is the average of hourly temp readings during a 24 hour period
35
daily total rainfall def
amount less than 0.05mm is trace solid precipitation included (snow, hail) which is melted before being included in any measurements
36
daily total sunshine def
recorded to nearest tenth of an hour
37
daily mean wind direction and windspeed def
in knots averaged over 24 hours mean wind directions are given as bearings and as cardinal (compass) directions
38
beaufort scale
the data for mean windspeed is also categorized according to it
39
knots def
Kn nautical mile per hour 1Kn=1.15mph
40
daily maximum gust in knots
the highest instantaneous windspeed recorded and the direction from which it is blowing
41
daily maximum relative humidity
given as a percentage of air saturation with water vapor
42
beaufort scale 0 1-3 4 5
calm- less than 1 knot light- 1-10 knots moderate- 11-16 knots fresh- 17-21 knots
43
daily mean cloud cover
measured in oktas or eighths of the sky covered by cloud
44
daily mean visibility
measured In decameters (dm) this is the greatest horizontal distance at which an object can be seen in daylight
45
daily mean pressure
measured in hectopascals (hPa)
46
uk weather stations
camborne hurn heathrow leeming leuchars
47
overseas weather stations
beijing Jacksonville Perth
48
what stations in northern hemisphere
uk beijing Jackson ville
49
what stations in southern hemisphere
Perth
50
which hemisphere has which month summer and which month winter
Northern- July-september summer southern- july to September winter
51
which stations are coastal areas and what does that mean
camborne hurn leudhars Perth Jacksonville generally more windier
52
which stations are noncostal areas
Jacksonville beijing heathrow leeming
53
units of each daily mean temp daly total rainfall daily total sunshine daily maximum relative humidity daily mea visibility daily mean pressure daily mean total cloud daily maximum gust
.degrees celsius .mm .hours .percentage .dm (1dm= 10m) .hpa (1hpa=100pa) .oaths-discretee variable 0-8 .knots/ beautrfort scale doserete variable 13 variables 0-calm 12 hurricane
54
how to know sample for daily total rainfall generated is a random sample
does not include a 0
55
what does tr mean
trace amounts of daily total rainfall 0-0.05mm
56
if tr is included what to do
take it as a 0
57
how to write for ex sty 100 member of yacht club listed alaphetically committee wants to pick sample of 12 for questionnaire explain how calculator can take simple random sample
1. allocate a number from 1 to 100 to each member 2. use calculator to generate 12 random members from 1 - 100 3. select the members of yacht corespondant to chosen
58
ex styl q2 factory manager wants info about the ways their workers travel to work 480 workers and each has a working clocking in number from 1-480 explain how manager could take systematic sample of size 30
1. 480/30 = 16 2. calucator generates a random number from 1 to 16 3. select chosen number as first clocking in number and then select from every 16th clocking in number after chosen number until you reach sample size of 30
59
ex style 3 school decided to survey staff and students . explain why school decoded to take stratified sample of staff and students . suggest suitable sampling frame .identify sampling units there are 250 stud and 30 staff .explain how a sample could take stratified sample size of 60
1. obtain a representative sample of staff/stud 2. list of names of staff/stud 3. member of staff of stud 4. students 250/280 x 60= 54 staff 30/280 x 60= 6 5. allocate no from 1-280 to each staf/stud use calc tol generate 54 random number for students and 6 for staff take the numbers chosen

maths statistics year 1 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions