Exam 1: Introduction to Statistics

Determine whether the given description corresponds to an observational study or an experiment. -Patients with severe heart failure were randomly assigned to two treatment groups to compare death and hospitalization rates. One group was treated with drug therapy while the other group was treated with a combination of drugs and an electrical device.

The following questions relate to random samples and simple random samples. -To assess the variation in volume (in cubic centimeters) of different manufacturer's pre-filled hormone injections, reproductive biologists select every 50th syringe beginning at a random moment. Does this sampling plan result in a random sample? Simple random sample?

Identify the type of observational study: cross-sectional, retrospective, or prospective. -Geneticists studying the biodiversity of roses collect data from reports classifying the number of varieties during the past 30 years.

Determine the type of sampling used: systematic, convenience, stratified, or cluster. -To conduct a survey of the interest of U.S. citizens in Yellowstone National Park, a list of zipcodes is compiled. All citizens in 50 different zipcodes are selected to be mailed a survey.

Determine whether the given description corresponds to an observational study or an experiment. -In a study of cold symptoms, the body temperatures of study participants were taken.

Determine the type of sampling used: systematic, convenience, stratified, or cluster. -A county water quality control officer obtains a list of all residential addresses in the county and constructs a sample of homes to monitor by selecting every 200th home on the list.

Determine the type of sampling used: systematic, convenience, stratified, or cluster. -To obtain a sample of diabetics, a graduate student contacts nearby hospitals for a list of names.

Determine whether the given values are from a discrete or a continuous data set. -A sample of Dall sheep is measured to have an average (mean) horn length of 35.7 inches.

Determine the type of sampling used: systematic, convenience, stratified, or cluster. -To conduct a study of Johnson & Johnson shareholder attitudes, a list of shareholder zipcodes is compiled. All shareholders from 20 different zipcodes are selected to be surveyed.

Determine whether the given description corresponds to an observational study or an experiment. -Children with attention deficit hyperactivity disorder are randomly divided into four treatment groups (the Tomatis Method, the Dore Method, the Brain Gym, and a control group) to compare differences in focus and concentration.

Determine which of the four levels of measurement is most appropriate. -Scientists classify the four major deserts in North America using different regions: the Great Basin, the Mojave, the Sonoran, and the Chihuahuan. What type of data is collected?

Determine which of the four levels of measurement is most appropriate. -Physicians rank the severity of asthma using mild intermittent asthma, mild persistent asthma, moderate persistent asthma, severe persistent asthma, or brittle asthma. What type of data is collected?

Determine whether the given value is a statistic or a parameter. -Volunteers in Grayton Beach, FL identified the average (mean) number of hatchlings in all 79 Loggerhead turtle nests.

Determine which of the four levels of measurement is most appropriate. -Ornithologists classify hummingbirds in the United States using 17 different species: Allen, Anna, Berylline, Black-chinned, Blue-throated, Broad-billed, Broad- tailed, Buff-bellied, Calliope, Costa, Lucifer, Magnificent, Ruby-throated, Rufous, Violet-crowned, White-eared, and Xantus. What type of data is collected?

Determine the type of sampling used: systematic, convenience, stratified, or cluster. -Biologists studying the pH level of state waterways obtain a sample of streams from a randomly generated list by selecting every 5th stream on the list.

Determine whether the given value is a statistic or a parameter. -A sample of Medtronic's rechargeable implanted spine stimulator batteries lasted an average (mean) of nine years.