In hypothesis testing, two competing statements are formulated: the null hypothesis (H0) and the alternative hypothesis (H1). The null hypothesis represents a statement of no effect or no difference, serving as a default position that indicates no change in the population parameter being tested. The alternative hypothesis, conversely, suggests that there is an effect or a difference. It is what the researcher aims to support through evidence.
For example, if we want to test whether a new teaching method improves student performance, the null hypothesis might state that the average test scores of students using the new method are equal to those using the traditional method (H0: μ1 = μ2). The alternative hypothesis would state that the average test scores of students using the new method are different (H1: μ1 ≠ μ2).
In a practical context, such as evaluating a new product in the Kenyan market, the null hypothesis could assert that the new product has no impact on sales compared to the existing product, while the alternative hypothesis would claim that the new product does affect sales positively or negatively. Understanding these hypotheses is crucial for conducting valid statistical tests and making informed business decisions.