Suppose the following regression results have been calculated:

(3.29)

is a single (point) estimate of the unknown population parameter, β. As stated above, the reliability of the point estimate is measured by the coefficient’s standard error. The information from one or more of the sample coefficients and their standard errors can be used to make inferences about the population parameters. So the estimate of the slope coefficient is but it is obvious that this number is likely to vary to some degree from one sample to the next. It might be of interest to answer the question, ‘Is it plausible, given this estimate, that the true population parameter, β, could be 0.5? Is it plausible that β

could be 1?’, etc. Answers to these questions can be obtained through hypothesis testing.