Identify the independent and dependent variables for each study.

50. People who walk at least 3 miles a day are randomly selected, and their blood triglyceride levels are measured in order to determine if the number of miles that they walk has any influence on these levels.

Read the following details regarding the number of fatal accidents in the transportation industry for a specific year, and answer the question.

7. From the information given, comment on the relationship between the variables.

Classify as nominal-level, ordinal-level, interval-level, or ratio-level measurement.

27. Rating of cooked ribs at a rib cook-off

Telephone numbers, classify as nominal-level, ordinal-level, interval-level, or ratio-level measurements.

Blood types-O, A, B, AB, classify as nominal-level, ordinal-level, interval-level, or ratio-level measurements.

Suggest some confounding variables that the researcher might want to consider when doing a study.
York University in Toronto, Canada, stated that people who had suffered from fibromyalgia were able to reduce their pain by participating in twice-weekly yoga sessions.

Propose some confounding variables that the researcher might want to consider when doing a study.

A leading journal reported that people who have a more flexible work schedule are more satisfied with their jobs.

Suggest some confounding variables that the researcher might want to consider when doing a study.
Psychology Today magazine reports that the more intelligent a person is (based on $\mathrm{IQ}$), the more willing the person is to make a cooperative choice rather than a selfish one.

Select a newspaper or magazine article that involves a statistical study, and write a paper answering these questions.
a. Is this study descriptive or inferential? Explain your answer. b. What are the variables used in the study? In your opinion, what level of measurement was used to obtain the data from the variables? c. Does the article define the population? If so, how is it defined? If not, how could it be defined? d. Does the article state the sample size and how the sample was obtained? If so, determine the size of the sample and explain how it was selected. If not, suggest a way it could have been obtained. e. Explain in your own words what procedure (survey, comparison of groups, etc.) might have been used to determine the study's conclusions. f. Do you agree or disagree with the conclusions? State your reasons.

For the article that you selected in previous exercise, suggest some confounding variables that may have an effect on the results of the study.

For the article that you used in Exercise 43 , identify the independent variable(s) and dependent variable for the study.

Find an article that describes a statistical study, and identify the study as observational or experimental.

Find an article that describes a statistical study.

Is the study an observational study or an experiment? If it is an experiment, identify the treatment.

Give a reason why the statement made might be misleading.
Caffeine and Health In the $1980 \mathrm{~s}$, a study linked coffee to a higher risk of heart disease and pancreatic cancer. In the early $1990$s, studies showed that drinking coffee posed minimal health threats. However, in $1994,$ a study showed that pregnant women who drank $3$ or more cups of tea daily may be at risk for miscarriage. In $1998,$ a study claimed that women who drank more than a half-cup of caffeinated tea every day may actually increase their fertility. In $1998$, a study showed that over a lifetime, a few extra cups of coffee a day can raise blood pressure, heart rate, and stress (Source: "Bottom Line: Is It Good for You? Or Bad?"' by Monika Guttman, USA TODAY Weekend). Suggest some reasons why these studies appear to be conflicting.