Hockenbury Discovering Psychology 5th txtbk

30 CHAPTER 1 Introduction and Research MethodsExperimental (informed)group(44 participants)Session 1:Questionnaire andphysical measuresExercise informationand write-up(Independent variable)4-week intervalSession 2:Questionnaire andphysical measuresDebriefingParticipants:84 female hotel maidsRandom assignment byhotel to conditionsData analyzed andgroups comparedA potential confounding variable was that the housekeeping staff at a particularhotel might talk to each other about being in the study. This meant that the participantsat the different hotels could not be individually assigned to the experimentalor control groups. Instead, each hotel was randomly assigned to either the experimentalor the control condition (see Figure 1.5). Thus, all of the participants at agiven hotel were assigned to the same group.All of the participants were told that the experimenters were interested ingetting information on their health so that they could study ways to improve it.In return for their help, the participants would receive informationabout research on health and happiness at the end of the study.Control group(40 participants)The Independent Variable, Experimental Group,and Control GroupIn Crum and Langer’s experiment, the independent variable was beinginformed that housekeeping work was good exercise. Hence,the participants in the experimental group were dubbed “the informedgroup.”The informed group participants received a write-up discussingthe benefits of exercise. It was explained that their daily housekeepingchores satisfied, and even exceeded, government recommendationsfor healthy daily exercise to burn at least 200 calories. The averagecalories expended for different housekeeping activities werealso detailed. For example, changing bed linens for 15 minutes burns40 calories, vacuuming a room burns 50 calories, and so forth.The write-ups were read and explained to the staff. Each informedgroup participant also received a printed copy. And largeposters with the information were displayed on the bulletin boardsin the staff lounge. The posters functioned as a daily reminder ofhow much exercise the staff was getting in performing theirhousekeeping duties.In any well-designed experiment, there is at least one controlgroup. The control group serves as a baseline against which changesin the experimental group can be compared. In a typical experiment, the participantsassigned to the control group go through all the experimental phases butare not exposed to the independent variable. In Crum and Langer’s experiment, thecontrol group consisted of the participants who were not informed that their housekeepingwork was beneficial healthy exercise.Session 1:Questionnaire andphysical measuresNo information4-week intervalSession 2:Questionnaire andphysical measuresDebriefingFigure 1.5 The HotelExperiment DesignResults reportedcontrol group or control conditionIn an experiment, the group of participantswho are exposed to all experimental conditions,except the independent variable; thegroup against which changes in theexperimental group are compared.The Dependent Variables and Experimental ProcedureSeveral dependent variables were measured for change. All participants completeda questionnaire about whether they exercised regularly, how much exercisethey got, where they got their exercise, and so on. It was noted whetherparticipants already perceived their work-related activities as exercise. Thequestionnaire responses were used as measures of self-reported exercise and todetermine if participants perceived work as exercise. The questionnaire alsoasked about their diet during the previous month and personal habits, such asalcohol use and smoking.Each participant also completed various measures of physical health, includingweight, percentage of body fat, body mass index (BMI), waist-to-hip ratio, andblood pressure. After the measurements, the participants in the informed groupwere given the information and handouts about how their work was good exercise.The participants in the control group were not given this information.During the month-long study, all other conditions were held constant. The hotelmanagement confirmed that the workload of the housekeeping staff remainedconstant throughout the study. At the end of four weeks, the questionnaire andmeasures of physical health were administered again.