Researchers explored whether there were mean differences between students who were randomly assigned to take notes longhand and students who were randomly assigned to take notes on their laptops (Mueller & Oppenheimer, 2014). They had observed that students who took notes by hand performed better, on average, on conceptual questions— those that involved thinking beyond just recalling facts—than students who took notes on their laptops. To explore reasons for this difference, they examined the students’ notes. The researchers “found that laptop notes contained an average of 14.6% verbatim overlap with the lecture (SD = 7.3%), whereas longhand notes averaged only 8.8% (SD = 4.8%), t(63) = −3.77, p < .001, d = 0.94” (p. 3). They concluded that when people took notes longhand, they were more likely to put ideas in their own words, which likely led to deeper processing and better learning of information.

a. What kind of t test did the researchers use? Explain your answer.

b. How do we know this finding is statistically significant?

c. How many participants were in this experiment?

d. Identify the means of the two groups.

e. What is the effect size for this finding? Interpret what that means in terms of Cohen’s conventions.