Читать книгу Statistics and Probability with Applications for Engineers and Scientists Using MINITAB, R and JMP - Bhisham C. Gupta, Irwin Guttman - Страница 114

In day‐to‐day activities and decisions, we often confront two scenarios: one where we are certain about the outcome of our action and the other where we are uncertain or at a loss. For example, in making a decision about outcomes, an engineer knows that a computer motherboard requires four RAM chips and plans to manufacture 100 motherboards. On the one hand, the engineer is certain that he will need 400 RAM chips. On the other hand, the manufacturing process of the RAM chips produces both nondefective and defective chips. Thus, the engineer has to focus on how many defective chips could be produced at the end of a given shift and so she is dealing with uncertainty.

Probability is a measure of chance. Chance, in this context, means there is a possibility that some sort of event will occur or will not occur. For example, the manager needs to determine the probability that the manufacturing process of RAM chips will produce 10 defective chips in a given shift. In other words, one would like to measure the chance that in reality, the manufacturing process of RAM chips does produce 10 defective chips in a given shift. This small example shows that the theory of probability plays a fundamental role in dealing with problems where there is any kind of uncertainty.