An experimenter investigated the effects of a sensitivity-training course on policemen's effectiveness at resolving

domestic disputes (using independent samples who had or had not completed the course). The dependent variable was

the ability to resolve domestic disputes. These success scores were obtained:

No Course: 11, 14, 10, 12, 8, 15, 12, 13, 9 11

Course: 13, 16, 14, 17, 11, 14, 15, 18, 12, 11