# the dependent variable

Assume that student volunteers were assigned arbitrarily (according to a coin toss) either to be trained to meditate or to behave as usual. To deter-mine whether meditation training (the independent variable) inﬂuences GPAs (the dependent variable), GPAs were calculated for each student at the end of the one-year experiment, yielding these results for the two groups:

NONMEDITATORS

3.67 3.79 3.00

2.50 2.75 1.90

2.80 2.65 2.58

2.83 3.10 3.37

3.25 2.76 2.86

2.90 2.10 2.66

2.34 3.20 2.67

3.59 3.00 3.08

MEDITATORS

3.57 2.45 3.75

3.50 2.67 2.90

2.95 3.30 3.56

3.56 3.78 3.75

3.56 3.78 3.75

3.45 3.00 3.35

3.10 2.75 3.09

2.58 2.95 3.56

3.30 3.43 3.47

DESCRIBING DATA WITH TABLES AND GRAPHS

(a) What is the unit of measurement for these data?

(b) Construct separate frequency distributions for meditators and for non-meditators. (First, construct the frequency distribution for the group having the larger range. Then, to facilitate comparisons, use the same set of classes for the other frequency distribution.)

(c) Do the two groups tend to differ? (Eventually, tools from inferential statistics, as described in Part 2, will help you decide whether any apparent difference between the two groups probably is real or merely transitory, that is, attributable to variability or chance. See Review Question 14.15 on page 324.)