You are investigating methods for reducing the number of stray dogs in cities. You get solid data on stray animals for every city and find that the lowest rate (per capita) of stray dogs is found in some of the smallest cities you studied. You are tempted to conclude that small cities must do a better job of handling stray animals. But first you decide to check to see if this result might simply be due to the law of large numbers instead. Which of the following methods would most help you answer that question?
A. check to see if the cities with the highest rate of stray dogs are also among the smallest cities
B. ensure that your method of identifying cities does not create a selection effect
C. make sure you are looking at a large enough number of cities
D. it can't be the law of large numbers, because that would only affect large cities
Answer: A. check to see if the cities with the highest rate of stray dogs are also among the smallest cities
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Zarathustra means:
a. "White Star" b. "running horse" c. "yellow camel" d. "Wise Lord"
Answer the following statement(s) true (T) or false (F)
1. In Louisa Locke's Maids of Fortune, Annie's house is a symbol of her independence. 2. In "The Woman Destroyed," Monique plots to kill her husband because of his infidelity, but she kills his girlfriend instead. 3. In Hosseini's A Thousand Splendid Suns, Rasheed's love for Maryam only increases after she has his son.
Nanak took this principle belief from Islam when developing Sikhism
a. that there is one true God b. the idea of ahimsa, or non-injury c. vegetarianism d. ceremonialism and rituals
Read and discuss the following report. In your discussion, identify the experimental and control groups, say whether there may be confounding variables in the study, and determine what the outcome probably was. (What does "no statistically significant difference" probably mean as it is used near the end of the report?)"A report released today said that a small, controlled study found magnets were no more effective than sham devices in treating chronic lower back pain.""But researchers note in the Journal of the American Medical Association that the negative result from an experiment with just 20 patients doesn't rule out the possibilities that magnets can help lower back pain or that magnet therapy can really work.Such therapy has gained enormous popularity in recent years, despite
little scientific evidence that the treatments work to relieve pain, improve circulation, or offer any other health benefits.Celebrities, scores of books, and hundreds of Web sites promote the treatments, even though the Food and Drug Administration forbids any healing benefits to be claimed for them. By some estimates, more than $5 billion worth of therapeutic magnets have been sold worldwide.A number of formal experiments, several supported by the National Institutes of Health, are under way to test magnets on a variety of painful chronic conditions.The latest study, carried out by Dr. Edward Collacott of the Veterans Affairs Medical Center in Prescott, Arizona, and colleagues, is thought to be the first published experiment to use active and inactive magnets for more than a single episode of treatment, and for longer than 45 minutes.All the patients in the study group had lower back pain, including the deformation of at least one articulating part of a vertebra. They had experienced pain in the same area of the back for an average of 19 years.Each patient wore a flexible, rubberlike device for a total of six hours a day, three days a week, for two weeks. Each used an active bipolar magnet and an identical-looking, de-magnetized device for one week, but neither the patients nor the doctors treating them knew which therapy was being used.The patients were questioned about their pain using a standardized questionnaire for pain measurement. Doctors also examined the patients more formally to determine the range of motion in the lower spine.At the end of the study, the researchers found 'no statistically significant difference' between patients when they'd been wearing the real magnets or shams.Collacott and his coauthors said more studies should be done to verify their results.This was a pilot study and was not intended to prove or disprove the effectiveness of magnet therapy in general. Additional studies using different magnets, treatment times, and patient populations are needed."-Scripps Howard News Service What will be an ideal response?