Null and Alternative Hypothesis - Individual significance Now, in the previous case, you are introduced to a new variable, shoe year (Y) which signifies when the shoe was originally launched. You now want to test whether Y has any significant impact on sales. What would be your null and alternative hypotheses in this case? Null hypothesis: Y= 0, Y has no significance Alternative hypothesis: Y 0. Y is non-zero May not be applicable to Multiple Linear Regression