Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Grouped data
Where f = frequency of the variable, μ= population mean.
Example 17
A security analyst studied hundred companies and obtained the following Return on Investment (ROI) data for the year 20x3.
Returns %
0-10
10-20
20-30
30-40
No. of companies
19
32
41
8
We can find how the ROI of the company varies with the mean ROI by calculating the standard deviations for the above data.
The steps involved are:
Find mean for grouped data.
Find deviations from mean for grouped data.
Find squares of the above deviations.
Total the squared deviations taking frequency into account.
Calculate square root.
Return on investment
Mid-point
Deviation
%
X
f
fX
X - μ
f(X - μ )2
5
95
-13.8
3618.36
15
480
-3.8
462.08
25
1025
6.2
1576.04
35
280
16.2
2099.52
Total
100
1880
7756.00
=
Thus, the standard deviation for the return on investment is 8.8%.
In such a calculation, we always assume that all the observations in a class interval are located at the mid-point of the class. For example, the first class interval has mid-point 5 and frequency 19. Hence the assumption is that all the 19 companies have an ROI of exactly 5%.
Disadvantages For calculating median it is necessary to arrange the data; other averages do not need any arrangement. Since it is a positional average, its value is not d
applications of normal probability distribution
What is an interaction? Describe an example and identify the variables within your population (work, social, academic, etc.) for which you might expect interactions?
Assumptions in Regression To understand the properties underlying the regression line, let us go back to the example of model exam and main exam. Now we can find an estimate o
Consider the following game: (a) If (top, left) is a Weakly Dominant Strategy Equilibrium, then what inequalities must hold among (a, ..., h)? (b) If (top, left) is a Na
The PCA is amongst the oldest of the multivariate statistical methods of data reduction. It is a technique for simplifying a dataset, by reducing multidimensional datasets to lower
Cause and Effect Even a highly significant correlation does not necessarily mean that a cause and effect relationship exists between the two variables. Thus, correlation does
Importance of official statistic
Advantages It is especially useful in case of open-end classes since only the position and not the values of items must be known. The median is also recommended if th
Types of business forecasting are generally as follows: 1. Sales and Demand forecasts 2. Porduction forecasts. 3. Cost Forecasts 4. Financi
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd