Unit 5: Quantitative Techniques for Business
Frequency (1)
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This session looks at frequency, tabulation of data, grouping of data and class boundaries.
Click here to see the slides from the lesson.
Download the "Happy Shopper" exercise in pdf format (185Kb).
Download the "Magic Moments " exercise in pdf format (135Kb).
The Human Brain
The human brain finds it difficult to make sense of a large quantity of data, however once it is organised and presented, a large amount of information can be derived from it.
Data Classification
- Qualitative
- Qualitative data is data which is not numerically significant.
- colour of cars
- feelings about a new product
- taste
- thoughts on the ride
- Qualitative data is data which is not numerically significant.
- Quantitative
- Quantitative data is data which is expressed in numerical
terms
- number of hours worked
- amount spent
- cups of coffee drunk
- number of cars passing per hour
- Quantitative data is data which is expressed in numerical
terms
Data Classification
- Continuous Data
- data that is measured on an interval scale (such as length or weight)
- Discrete Data
- whole values (obtained by counting)
- Ordinal Data
- given a numerical value but only for comparative purposes (giving a score between 1 and 10).
- Categorical Data
- no numerical value (such as choice of newspaper)
How would you define the following?:
- heights of checkout operators
- choice of summer fruit
- sales of summer fruit per day
- weekly earnings by employees in Asda
- number of shoppers per day at Tesco
- market research survey into consumer reaction to a new product
Method of Travel
|
Person |
Mode of Travel |
Person |
Mode of Travel |
Person |
Mode of Travel |
Person |
Mode of Travel |
|
1 |
car |
6 |
car |
11 |
bus |
16 |
car |
|
2 |
car |
7 |
cycle |
12 |
car |
17 |
car |
|
3 |
bus |
8 |
bus |
13 |
walk |
18 |
car |
|
4 |
walk |
9 |
train |
14 |
walk |
19 |
bus |
|
5 |
cycle |
10 |
walk |
15 |
cycle |
20 |
car |
Tabulation of Data
|
Mode of Travel |
Frequency |
Relative Frequency |
|
Car |
8 |
40% |
|
Bus |
4 |
20% |
|
Walk |
4 |
20% |
|
Cycle |
3 |
15% |
|
Train |
1 |
5% |
Grouping
- Ungrouped
- all numbers are included to measure the frequency
- Grouped
- intervals are used to measure the frequency
 |
Class Boundary
- class boundaries and intervals
- these should be a convenient number such as 10,20, 25
- for example with a data range of 100 to 298 you could have
100-119, 120-129, 130-139, 140-149
and so on...
Irregular Intervals
A histogram is a variation of a bar chart in which it is the area (not the height) which represents the frequency. With regular class intervals the height is directly proportional to the class frequency, with irregular intervals (e.g. age) it may be appropriate to increase class widths.
Regular Intervals
Irregular Intervals
|
Daily Sales (£) |
No. of Stores |
|
Up to 1,999 |
10 |
|
2,000-3,999 |
40 |
|
4,000-7,999 |
100 |
|
8,000-11,999 |
120 |
|
12,000-19,999 |
60 |
