Statistical significance of the slope
Remember that the slope determines the relationship between the X and Y variables.
To check the significance of the slope of the variables' relationship and the viability to build a predictive model, we are going to use the t-test. The t-test requires two hypotheses:
- H0 – null hypothesis: The slope equals zero. This means that there is no relationship between the variables.
- HA – alternative hypothesis: The slope is NOT equal to zero. This means that the variables have a relationship.
The t-test calculation steps are as follows:
- Calculate the s value by dividing the SSE by the number of data elements minus two. In this example, the number of elements of data is 159.
- Divide the slope by the s value.
- Check whether the t-test is greater than the critical value given by the t-test table (https://www.sjsu.edu/faculty/gerstman/StatPrimer/t-table.pdf). If the value is greater than the critical...