Lock5withR (version 1.2.2)

MindsetMatters: Mindset Matters


Data from a study of perceived exercise with maids



A data frame with 75 observations on the following 14 variables.
  • Condition Treatment condition: uninformed or informed
  • Cond Treatment condition: 0=uninformed or 1=informed
  • Age Age (in years)
  • Wt Original weight (in pounds)
  • Wt2 Weight after 4 weeks (in pounds
  • BMI Original body mass index
  • BMI2 Body mass index after 4 weeks
  • Fat Original body fat percentage
  • Fat2 Body fat percentage after 4 weeks
  • WHR Original waist to hip ratio
  • WHR2 Waist to hip ratio
  • Syst Original systolic blood pressure
  • Syst2 Systolic blood pressure after 4 weeks
  • Diast Original diastolic blood pressure
  • Diast2 Diastolic blood pressure after 4 weeks


Crum, A.J. and Langer, E.J. (2007). Mind-Set Matters: Exercise and the Placebo Effect, Psychological Science, 18:165-171. Thanks to the authors for supplying the data.


In 2007 a Harvard psychologist recruited 75 female maids working in different hotels to participate in a study. She informed 41 maids (randomly chosen) that the work they do satisfies the Surgeon General's recommendations for an active lifestyle (which is true), giving them examples for how why their work is good exercise. The other 34 maids were told nothing (uninformed). Various chacteristics (weight, body mass index, ...) were recorded for each subject at the start of the experiment and again four weeks later. Maids with missing values for weight change have been removed.


Run this code


Run the code above in your browser using DataCamp Workspace