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%.
In this problem, we use the CSDATA data set, which is available in 'CSDATA.txt'. We do ne an indicator variable, say HIGPA, to be 1 if the GPA is 3.0 or better and 0 other- wise. S
Examining the Population Variance Business decision making does not limit itself to setting up the hypothesis to test for the equality of more than two means or proportions sim
If the economy does well, the investor's wealth is 2 and if the economy does poorly the investor's wealth is 1. Both outcomes are equally likely. The investor is offered to invest
The score distribution shown in the table is for all students who took a yearly AP statistical exam. An AP statistics teacher had 59 students preparing to take the AP exam. Though
There are two diagnostic tests for a disease. Among those who have the disease, 10% give negative results on the first test, and independently of this, 5% give negative results on
Different analyses of recurrent events data: The bladder cancer data listed in Wei, Lin, and Weissfeld (1989) is used in Example 54.8/49.8 of SAS to illustrate different anal
Ask question #MinimumA wedge is small piece of material having two of their opposite faces not parallel. To lift block of weight W, it is pushed by horizontal force P which lifts t
Measurement of trend , least square method
How to a calculate the combined standard deviation for five groups (samples)?
The Null Hypothesis - H0: The random errors will be normally distributed The Alternative Hypothesis - H1: The random errors are not normally distributed Reject H0: when P-v
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