Duration of an activity has the following estimates: Optimistic – 3 days; Most Likely – 5 days; Pessimistic – 13 days. The time estimate for that activity based on the triangular distribution is
Well I am also very confused with Beta and Triangular distribuition and all I know is they are probability distribution and related to Perform Quantitative Analysis.
I have read it a couple of times but it doesnt seem to get in my head.
All I know is the formula for expected duration (Mean) for Triagular distribution is P+M+O/3 , this will give you
13+5+3/3 = 7.
The formula for Variance for Triangular distribution = [(O-P)^2 + (M-P) * (M-O)]/18. ( I dont plan to remember this formula as I dont think it will be ever asked in the real exam, has anyone encountered it?)
Formula for Beta Distribution is same like PERT:
Mean = P+4M+O/6
Standard Deviation = P-O/6
and
Variance = SD square
Note: P = Pessimistic, O - Optimistic and M - Most Likely.
kang
Sun, 02/03/2013 - 06:49
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Duration of an activity has
Duration of an activity has the following estimates: Optimistic – 3 days; Most Likely – 5 days; Pessimistic – 13 days. The time estimate for that activity based on the triangular distribution is
Choose one answer.answer is A...i marked C
a. 7 days
b. 5 days
c. 6 days
d. 3 days
raza82
Sun, 02/03/2013 - 07:20
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Answer is a)
Well I am also very confused with Beta and Triangular distribuition and all I know is they are probability distribution and related to Perform Quantitative Analysis.
A detailed explaination is given here
http://www.deepfriedbrainproject.com/2010/07/probability-and-statistics-...
I have read it a couple of times but it doesnt seem to get in my head.
All I know is the formula for expected duration (Mean) for Triagular distribution is P+M+O/3 , this will give you
13+5+3/3 = 7.
The formula for Variance for Triangular distribution = [(O-P)^2 + (M-P) * (M-O)]/18. ( I dont plan to remember this formula as I dont think it will be ever asked in the real exam, has anyone encountered it?)
Formula for Beta Distribution is same like PERT:
Mean = P+4M+O/6
Standard Deviation = P-O/6
and
Variance = SD square
Note: P = Pessimistic, O - Optimistic and M - Most Likely.