According to a home securities company, the highest percentage of home burglaries occur during the summer months. Local police conducted a study of home burglaries for a ten-year period. A computer program randomly selected 1500 home burglaries and both the month of burglary and amount of insurance claim were recorded. Of the 1500 home burglaries analyzed in the study, 39% of burglaries occurred in summer months (June, July, August). The average insurance claim was $2,100.
Is the following critique of the study valid or invalid? A city council member argues that the study results can’t be projected onto all local home burglaries because the sample burglaries were not selected fairly.
a. valid
b. invalid