Practical Spreadsheet Risk Modeling for Management

154 Practical Spreadsheet Risk Modeling for Management

condence interval does not contain zero, then we are at least 95% condent

that the variable is either positively or negatively related to the response vari-

able. (In this case, there is a positive association between advertising and

sales.) The corresponding P-value will be less than 5%. Whenever the 95%

condence interval includes the value zero, then the P-value will be greater

than 5%, and we cannot say that there is a signicant association between

the independent and dependent variables.

Use of 5% at the critical P-value for determining statistical signicance is

fairly standard