In PERT network analysis, which type of resulting distribution for an activity completion duration is assumed?

PERT Network Analysis

In PERT (Program Evaluation and Review Technique) network analysis, the duration of an activity is considered as a random variable. The technique is used to represent and analyze the tasks involved in completing a project. To model the uncertainty in activity durations, PERT uses a specific type of probability distribution.

Analyzing the Given Options

1. Option 1: Chi-square distribution (Incorrect)

   Chi-square distribution is primarily used in hypothesis testing and in construction of confidence intervals. It is not suitable for representing the distribution of activity durations in PERT.

2. Option 2: Beta distribution (Correct)

   PERT assumes that the activity durations follow a Beta distribution. This distribution is flexible and can take various shapes depending on the values of its parameters. It is particularly useful for modeling the uncertain nature of activity durations in project management.

3. Option 3: Alpha distribution (Incorrect)

   Alpha distribution is not a standard term in probability and statistics. There is no well-defined distribution known as the Alpha distribution, making this option incorrect.

4. Option 4: Gamma distribution (Incorrect)

   Gamma distribution is used in various fields for modeling positively skewed data, but it is not specifically used in PERT for activity duration estimation.