For each of the following studies, say whether you would employ the t test for dependent means or a t test for independent means. Column preview A researcher determines the heights of 40 university students who are the firstborn in their families as well as compares the 15 who come from large fami- lies to the 25 who come from smaller families. t test for independent means A researcher tests performance on the math skills test of each of 250 individuals before and after they complete the one-day seminar on managing test anxiety. t test for dependent means A researcher compares the resting heart rate of 15 individuals who have been taking a particular drug to the resting heart rate of 48 other individuals who have not been taking the drug.