Business Decision Making

This document provides study material and solved assignments for Business Decision Making. It covers topics such as ungrouped and grouped descriptive statistics, relationships, networking, and more. The document includes tasks with explanations and calculations.

Business Decision Making
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Contents
Task 1: Ungrouped Descriptive Statistics........................................................................................3
1. Find out following:.............................................................................................................3
Mean:......................................................................................................................................3
Minimum:...............................................................................................................................3
Standard deviation:.................................................................................................................3
Coefficient of variation:.........................................................................................................3
2..............................................................................................................................................3
Task 2: Grouped Descriptive Statistics............................................................................................4
1. Summarising grouped data:................................................................................................4
2..............................................................................................................................................5
3. Linear interpolation:...........................................................................................................6
4..............................................................................................................................................6
Task 3: Relationships.......................................................................................................................7
1..............................................................................................................................................7
2..............................................................................................................................................7
3..............................................................................................................................................7
4..............................................................................................................................................7
Task 4: Networking..........................................................................................................................8
1..............................................................................................................................................8
2..............................................................................................................................................8
3..............................................................................................................................................8
Task 5...............................................................................................................................................9
1..............................................................................................................................................9
2..............................................................................................................................................9
3..............................................................................................................................................9
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Task 1: Ungrouped Descriptive Statistics
1. Find out following:
Mean:
Sum = 4702
Total sample size = 120
Mean = Sum / sample size
= 4702 / 120
= 39.1833
The resulted mean depicts that average age of the Netflix’s viewer is around 39.1833 or 390
years.
Minimum:
Range = Maximum – Minimum
65 = 80 – Minimum
Thus, the minimum = 80 – 65 = 15
Standard deviation:
Standard deviation = √variance
= √163.4
= 12.7828
The standard deviation figure computed above depicts that aggregate variance of age of viewers
age varies by 12.7828.
Coefficient of variation:
Coefficient of variance = standard deviation / mean
= (12.7828/ 39.1833) × 100
= 32.62%
The resulted COV shows that average age of Netflix viewers deviated from the mean value by
32.62%. Which indicates that mostly viewers are of age around 39 years.
2.
The mean value of sample of 120 subscribers is 39.18 which shows that most common viewer age
of Netflix is 39 years. While Median of the data set is 43 which merely describes that in selected
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sample most central figure of age is 43. Since there is not a larger gap between age derived from
mean and median, the distribution of data is quite relevant and having significance for users.
Task 2: Grouped Descriptive Statistics
1. Summarising grouped data:
Age
Category
Frequency C.f. % C.f.
Under 25 9 9 7.50%
25 to 34 27 36 30.00%
35 to 44 30 66 55.00%
45 to 54 24 90 75.00%
55 and
over
30 120 100.00%
Total: 120
b)
Age
Category Mid-term (x) Frequency (f) xf
16 to 25 20.5 9 184.5
25 to 34 29.5 27 796.5
35 to 44 39.5 30 1185
45 to 54 49.5 24 1188
55 to 64 59.5 30 1785
Total: 120 5139
Mean (x¯) = ∑xf / ∑f
5139 / 120
42.825
Age Mid-term (x) Frequency (f) xf (Mean - f(Mean -
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Category x)2 x)2
16 to 25 20.5 9 184.5 498.4056 4485.651
25 to 34 29.5 27 796.5 177.5556 4794.002
35 to 44 39.5 30 1185 11.05563 331.6688
45 to 54 49.5 24 1188 44.55563 1069.335
55 to 64 59.5 30 1785 278.0556 8341.669
Total: 120 5139 19022.33
Standard deviation =
= √19022.33/120
= 158.519375
= 12.590
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As assessed in task 1, the mean and standard deviation values are 39.1833 and 12.7828. Whereas
computed figure of mean and SD in Task 2 is 42.825 and 12.590. Here notable aspect is that in
case of grouped statistics, accuracy of mean and standard deviation is quite relevant than
ungroup statistics since in group statistics frequency and cumulative frequencies are considered
which provide more meaningful and accurate outcomes.
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3. Linear interpolation:
By linear interpolation the given data shows that median value of the data set is near to 39.5.
4.
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Task 3: Relationships
1.
Here best identified predictor variable here is for the regression analysis is the Age factor.
The choice of such a variable is based on perfect negative relationship among Job
Separations Probabilities and the age factors. The relationship clearly reveals that when one gets
older, the likelihood of job separations decreases. Other factors, on other hand, do not seem to
have a consistent positively or negatively relationship with the job separation.
2.
3.
The computed coefficient of determination based on given data is 0.724. Such outcome is nearly
equivalent to the data set’s correlation coefficient i.e. 0.85. Here notable aspect is that value
obtained of correlation is closer to 1; which describes that there’s nearly a perfect relationship
among age and the job-separations probabilities.
4.
Based on given data, derived regression equation using scatter diagram is as follows:
‘y = -0.006x + 0.551’.
The above stated equation depicts that here both Age as well as Job separations probabilities
have negative relationship. Which implies that means as the figures of age rise; the probability of
the Job Separation will also decline.
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Task 4: Networking
1.
2.
The overall duration of project is around 16 weeks; that is minimum required time taken which is
relevant for the project to be completed:
Here are two major critical paths:
1. S→A→C→E→F→H
2. S→B→E→F→H
3.
The beginning and end times of critical tasks must be strictly adhered to. They are important in
the way that their failure causes the entire project to be delayed. To some extent, start time
regarding non-critical tasks may be freely chosen. In above stated diagram; D→G→H is
regarded as non-critical activities as well as can be put on holding if required.
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Task 5
1.
In the entire study assessment, Task 1 and 2 has been done well specifically. The reason behind
the effective accomplishment of these task is that these tasks are done based on specific formula.
2.
In the assessment, Task 3 is most challenging task in which Network diagram has been prepared.
The reason behind this is that the network diagram here is prepared in excel and we have less
expertise in preparation of this network diagram.
3.
I would like to prepare and interpret scatter diagram as done in Task 3 in more professional
manner using more relevant analysis. Also, want to make sure that best predictor we have chosen
is relevant for large group of users.
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