Question

Refer to the following excerpt from a hypothetical research article that compared memory test performance between two groups of participants: those who consumed a caffeinated beverage before the test and those who consumed a non-caffeinated beverage: An independent samples t-test was conducted to examine the difference between experimental conditions on test performance. The results indicated a significant difference between participants who consumed the caffeinated beverage and participants who did not, with participants in the caffeinated group (M = 7.64, SD = 2.41) performing worse than participants in the non-caffeinated group (M = 9.81, SD = 3.16), t(97) = 2.14, p < .05. Write a brief paper explaining what the author means when she says that the results were statistically significant. In other words, what does it mean to say that results are statistically significant? Be sure to explain what a p value is and how it relates to statistical significance.

Answer 1

Answer: In statistics, a result or effect is statistically significant when it is unlikely to have been due to change. A "statistically significant difference" only means that there is statistical evidence that there is a difference; it does not mean that the difference is large, important or radically different. The lower the p-value, the more significant the result is.