Let X denote the data transfer time (ms) in a grid computing system (t

tbbfiladelfia6l

tbbfiladelfia6l

Answered question

2021-11-28

Let X denote the data transfer time (ms) in a grid computing system (the time required for data transfer between a “worker” computer and a “master” computer.
Suppose that X has a gamma distribution with mean value 37.5 ms and standard deviation 21.6 (suggested by the article “Computation Time of Grid Computing with Data Transfer Times that Follow a Gamma Distribution,” Proceedings of the First International Conference on Semantics, Knowledge, and Grid, 2005).
a. What are the values of a and b?
b. What is the probability that data transfer time exceeds 50 ms?

Answer & Explanation

Blanche McClain

Blanche McClain

Beginner2021-11-29Added 15 answers

Part a
The random variable X represents the data transfer time in a grid computing system.
It is given that the random variable X has a gamma distribution with mean value 37.5 ms and standard deviation 21.6.
The mean and variance of a gamma variate with parameters α and β are μ=αβ and σ2=αβ2.
Thus, the values of α and β is obtained in the following steps:
Consider the ratio,
σ2μ=αβ2αβ=β
β=σ2μ [substitute σ=21.6,μ=37.5]
=(21.6)237.5
=466.5637.5
=12.4416
Step 2
The value of β is 12.4416. The value of α is obtained as 3.0141 in the following steps:
μ=αβ
α=μβ
=37.512.4416
=3.014082
3.0141
Part b
Computing the probability that data transfer time exceeds 50ms:
z-score:
If a random variable X has a distribution with
zscore=XμσN(0,1)
z=5037.521.6
=0.58
Observe the value in the z-table corresponding to the (z=0.58) to obtain the area of the left side of (z=0.58).
The area for the left side of (z=0.58) is 0.7190.
Subtract 0.7190 from 1 to evaluate the total area of the (z=0.58).
Probability =10.7190
Therefore the probability that data transfer time exceeds 50 ms is 0.281

Do you have a similar question?

Recalculate according to your conditions!

New Questions in High school statistics

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?