Probability and Statistics

2

Probability Distribution

2.1 Introduction

Often we have to measure many different variables, e.g., the output voltage of a system, the strength of a team or the cost of a project. Further, we have to know the probability that a variable falls within a given range (0 to 1). The way the probability is distributed across various ranges of values gives rise to the concept of a probability distribution. The probability distribution or simply distribution shows the probabilities of events in an experiment.

2.2 Random Variables

Quantities whose variation has an element of chance are called random variables. Some examples are as follows:

1. The length of time during which a product is in working condition.
2. The force required to stretch a spring ...