1. Intro to Stats and Collecting Data

Why is a sample used more often than a population?

Determine whether the data set is a population or a sample. Explain your reasoning.

The amount spent by every tenth person cashing out at a store

Determine whether the statement is true or false. If it is false, rewrite it as a true statement.

The method for selecting a stratified sample is to order a population in some way and then select members of the population at regular intervals.

Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.

Questioning university students as they leave a college cafeteria, a researcher asks 342 students about their eating habits.

Determine whether you would take a census or use a sampling. If you would use a sampling, determine which sampling technique you would use. Explain.

The average distance traveled to a stadium by 55,000 spectators

Determine whether you would take a census or use a sampling. If you would use a sampling, determine which sampling technique you would use. Explain.

The average GPA of the 85 students on a college football team roster

Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.

Soybeans are planted on a 48-acre field. The field is divided into one-acre subplots. A sample is taken from each subplot to estimate the harvest.

In Exercises 1 and 2, identify the sampling technique used, and discuss potential sources of bias (if any). Explain.

Using random digit dialing, researchers asked 1090 U.S. adults their level of education.

Identify the sampling technique used in each study. Explain your reasoning.

A journalist asks people at a campground about air pollution.

An experiment is performed to test the effects of a new drug on attention-deficit/hyperactivity disorder (ADHD). The experimenter identifies 320 people ages 7 to 44 with ADHD to participate in the experiment. The subjects are divided into equal groups according to age. Within each group, subjects are then randomly selected to be in either the treatment group or the control group. What type of experimental design is being used for this experiment?

Identify the sampling technique used in each study. Explain your reasoning.

A study on attitudes about smoking is conducted at a college. The students are divided by class (freshman, sophomore, junior, and senior). Then a random sample is selected from each class and interviewed.

Which technique used in Exercise 7 could lead to a biased study? Explain.

Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.

Questioning teachers as they leave a faculty lounge, a researcher asks 45 of them about their teaching styles.

200 students volunteer for an experiment to test the effects of sleep deprivation on memory recall. The students will be placed in one of five different treatment groups, including the control group.

Explain how you could design an experiment so that it uses a randomized block design.

200 students volunteer for an experiment to test the effects of sleep deprivation on memory recall. The students will be placed in one of five different treatment groups, including the control group.

Explain how you could design an experiment so that it uses a completely randomized design.