Question: Define null hypothesis, alternative hypothesis, level of significance, test statistic, p value, and statistical significance.

• The null hypothesis (H0 ) is a statement about a population parameter, such as the population mean, that is assumed to be true.

• The alternative hypothesis (H1) is a statement that directly contradicts a null hypothesis by stating that the actual value of a population parameter, such as the mean, is less than, greater than, or not equal to the value stated in the null hypothesis.

• Level of significance is a criterion of judgment upon which a decision is made regarding the value stated in a null hypothesis. The criterion is based on the probability of obtaining a statistic measured in a sample if the value stated in the null hypothesis were true.

• The test statistic is a mathematical formula that allows researchers to determine the likelihood or probability of obtaining sample outcomes if the null hypothesis were true. The value of a test statistic can be used to make inferences concerning the value of a population parameter stated in the null hypothesis.

• A p value is the probability of obtaining a sample outcome, given that the value stated in the null hypothesis is true. The p value of a sample outcome is compared to the level of significance.

• Significance, or statistical significance, describes a decision made concerning a value stated in the null hypothesis. When a null hypothesis is rejected, a result is significant. When a null hypothesis is retained, a result is not significant.