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A proactive mindset increases the Circle of Concern and reduces the Circle of Influence.

A small city is considering building a community swimming pool using public funds. The city planner will survey a random sample of residents to ascertain support.  If she takes her random sample from a list of the parents of school children in the city school district, her sample may not be representative of all the residents of the city, so it will suffer from which problem?

The graph below shows marriage rates for women and men in the 50 U.S. states and the District of Columbia for 2014 (Source US Census Bureau). What is a plausible value for the correlation coefficient between marriage rates for US women and men in 2014?

The boxplots below display the annual per capital consumption of fruits and vegetables for 17 eastern states and 11 western states.  Select all of the following that are true.

A recent study indicated that the diabetes drug metformin (a glucose-lowering drug) appears to lower users’ risk of developing age-related diseases such as cancer, cardio-vascular disease, and dementia. The study followed diabetic men over the age of 65, all of whom had been prescribed a diabetes drug by their Veteran’s Administration hospital physicians. At the end of nine years, the researchers compared the rates at which the metformin users developed other diseases with that of the men who were taking a different diabetes drug.   Identify the Explanatory and Response variables.

Eighty-three healthy volunteers, aged 65 to 85, who ate fewer than 2 servings of fruits and vegetables per day, participated in a study. The participants were randomly assigned to one of two groups. One group was instructed to continue with their normal diet for sixteen weeks. The other group was instructed to included 5 or more portions of fruits and vegetables per day as part of their normal diet for the same sixteen weeks.  This is an example of which study design?

Existing data of biological attributes for alligators, such as snout length in inches and weight in pounds, can be used as indicators of restoration success in water quality. Suppose the weight is converted from pound to kilogram (1 kilogram  =  2.2 pounds approximately), the correlation  coefficient, r, between the height and length will

Researchers studying psychological stress have several variables they can use to measure stress.  Which one of the following variables is categorical?

The graph below shows per capita soft drink consumption versus median income, for the 48 contiguous U. S. states and the District of Columbia (Source: American Community Survey).                 What is a plausible value for the correlation between soft drink consumption and state median income?  

A researcher studied 500 pregnant American women throughout their pregnancies and recorded the amount of weight they gained, the weight of their newborn babies, whether or not they smoked, and how often they exercised. Which of the following is a categorical variable?