Exam 1: Data Collection

Determine whether the underlined value is a parameter or a statistic. -27.2% of the mayors of cities in a certain state are from minority groups.

Describe the Characteristics of an Experiment -__________ is a condition applied to the experimental units involved in an experiment.

Explain the Steps in Designing an Experiment -Which of the following is not true about factors

Distinguish Between an Observational Study and an Experiment -A poll is conducted in which professional musicians are asked their ages.

Determine the sampling technique which is used -In a recent online survey, participants were asked to answer yes or no to the question Are you in favor of stricter gun control 6571 responded yes while 5737 responded no . There was a fifty-cent charge for the call. What sampling technique was used

Distinguish Between an Observational Study and an Experiment -A scientist was studying the effects of a new fertilizer on crop yield. She randomly assigned half of the plots on a farm to group one and the remaining plots to group two. On the plots in group one, the new fertilizer was used for a year. On the plots in group two, the old fertilizer was used. At the end of the year the average crop yield for the plots in group one was compared with the average crop yield for the plots in group two.

Describe the Characteristics of an Experiment -An experiment in which the experimental unit (or subject) does not know which treatment he or she is receiving is called a ________________ .

Explain the Randomized Block Design -A farmer wishes to test the effects of a new fertilizer on her corn yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C s are treated with no fertilizer. At harvest time, the corn yield is recorded for each section of land. What is the response variable in this experiment

Explain the Completely Randomized Design -A drug company wanted to test a new indigestion medication. The researchers found 200 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose indigestion symptoms decreased was recorded and compared. What is the treatment in this experiment

Determine the Level of Measurement of a Variable -the day of the month

A study published in 1990 attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida beaches from environmental disasters. Forty-one hundred Florida residents were surveyed. Which of the following is the population used in the study

Determine the sampling technique which is used -The United States can be divided into four geographical regions: Northeast, South, Midwest, and West. The Northeast region consists of 9 states; the South region consists of 16 states; the Midwest consists of 12 states; and the West consists of 13 states. If a survey is to be administered to the governors of 10 of the states and we want equal representation for the states in each of the four regions, how many states from the South should be selected Round to the nearest whole state.

Explain the Sources of Bias in Sampling -Multiple choice questions on a test that include as one of the choices none of the above are an example of what type of question

Explain the Randomized Block Design -A farmer wishes to test the effects of a new fertilizer on her potato yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C s are treated with no fertilizer. At harvest time, the potato yield is recorded for each section of land. Identify the experimental units.

Provide an appropriate response. -The peak shopping time at a pet store is between 8-11:00 am on Saturday mornings. Management at the pet store randomly selected 35 customers last Saturday morning and decided to observe their shopping habits. They recorded the number of items that a sample of the customers purchased as well as the total time the customers spent in the store. Identify the types of variables recorded by the pet store.

Explain the Completely Randomized Design -A drug company wanted to test a new depression medication. The researchers found 700 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose depression symptoms decreased was recorded and compared. Identify the experimental units.

Classify the variable as qualitative or quantitative. -the number of seats in a school auditorium

Provide an appropriate response. -Classify the following random variable: telephone area codes

A telephone poll asked 1414 registered voters Would you vote for the current vice president if he ran for president Of these 1414 respondents, 34% would vote for the current vice president if he ran for president. The administrators of the study concluded that 34% of all registered voters would vote for the current vice president if he ran for president. Identify (a) the research objective, (b) the sample, (c) the descriptive statistics, and (d) the conclusions made in the study.

Determine whether the quantitative variable is discrete or continuous. -the cholesterol levels of a group of adults the day after Thanksgiving