Creation of Scatter Graph with Trend, Regression Equation and Coefficient of Determination

Assessment

Table of Contents
Table of Contents.............................................................................................................................2
Creation of scatter graph along with trend, regression equation and coefficient of
determination on the chart...........................................................................................................1
Stating the best predictor and the reason for the choice..............................................................1
Interpretation of the relevant correlation coefficient and the coefficient of determination.........2
Stating the regression equation in context and interpret the intercept and gradient....................3

MAIN BODY
TASK 1
1. Calculation
(a) Mean
Sum = 4972
Total sample size = 113
Mean = Sum / sample size
= 4972 / 113
= 44
The result shows that average age of Netflix viewer is around 44 years.
(b) Standard deviation =
=
= 12.91
The standard deviation result shows that total variance between viewers age varies by
12.91.
(c) Coefficient of variance = standard deviation / mean
= (12.91 / 44) × 100
= 29.34%
The result shows that on an average the age of viewers are deviated from mean by
29.34%. This indicates that most of the viewers have age around 44 years.
2. Comment on mean and the median values and comment on the distribution of the data.
On the basis of above computed values, this can be inferred that value of mean is of 44
and median is of 43.0. Both values are close together. While standard deviation is of
12.91 that shows that there is no relation between mean and standard deviation and data
is distributed in an unequal manner.
1

TASK 2
1. Using the frequency table above as a starting point and the tabular method for summarising
grouped data, construct two tables in Excel.
Age
Category Frequency C.f. % C.f.
Under 25 5 5 4.42%
25 to 34 26 31 27.43%
35 to 44 30 61 53.98%
45 to 54 26 87 76.99%
55 and over 26 113 100.00%
Total: 113
b)
Age
Category Mid-term (x) Frequency (f) xf
16 to 25 20.5 5 102.5
25 to 34 29.5 26 767
35 to 44 39.5 30 1185
45 to 54 49.5 26 1287
55 to 64 59.5 26 1547
Total: 113 4888.5
Mean (x ̄) = ∑xf / ∑f
4888.5 / 113
43.26106195
Age
Category Mid-term (x) Frequency (f) xf
Mean -
x
(Mean -
x)2 f(Mean -x)2
16 to 25 20.5 5 102.5 22.76 518.0176 2590.088
25 to 34 29.5 26 767 13.76 189.3376 4922.7776
35 to 44 39.5 30 1185 3.76 14.1376 424.128
45 to 54 49.5 26 1287 -6.24 38.9376 1012.3776
55 to 64 59.5 26 1547 -16.24 263.7376 6857.1776
Total: 113 4888.5 15806.5488
Standard deviation =
=
2