research methods review quiz 2

Experimental researchers must control _____ to protect internal validity.

confounding variables

In a simple experiment, the control group is used to:

Provide a baseline for comparison

Which of the examples below is active deception?

Rey, who tells participants he is studying their sportmanship when he is actually studying vengefulness

Joe studied the influence of room temperature on sleep quantity. Joe randomly assigned 40 people to sleep in a hot room and assigned another 40 people to sleep in a cool room. Both groups had people of various ages and genders. The hot rooms were noisy and the cool rooms were quiet. Joe then timed how long each participant slept. The independent variable was:

room temperature

Joe studied the influence of meditation on sleep quality. Joe assigned some participants to meditate before bedtime; other participants did not meditate before bedtime. Joe found that meditation caused improved sleep quality. The independent variable in this study was:

meditation

Joe studied the influence of music on nap length. Joe recruited participants and assigned them to either 1) listen to music or 2) not listen to music before taking a nap. People who listened to music gathered together to listen to the music and nap in a room at the Counseling Center. People who did not listen to music napped in their own homes. Everyone timed how long they napped. The variable that Joe failed to control was:

nap location

In correlational research, researchers are most interested in:

Observing naturally occurring relationship

Which of the following examples represents a positive correlation?

As study time increases, exam scores increase

A study examining the relationship between humor and memory compares memory performance scores for one group presented with funny sentences and a second group presented with not-funny sentences. The participants in both groups consist of a mixture of men and women. In this study, gender (men/women) is best characterized as:

an extraneous variable

Researchers who conduct experiments manipulate the ____ variable.

independent

Dr. Fowler is interested in studying how indoor lighting can influence people's moods during the winter. A sample of 100 households is selected. Fifty of the homes are randomly assigned to the bright-light condition where Dr. Fowler replaces all the lights with 100-watt bulbs. In the other 50 houses, all the lights are changed to 60-watt bulbs. After two months, Dr. Fowler measures the level of depression for the people living in the houses. In this study, the independent variable is the

brightness of the lights

Joe studied the influence of story length on memory for story content. Joe randomly assigned 50 adults to read a short story on a laptop computer screen. He assigned another 50 adults to read a long story printed on a sheet of paper. Everyone then took a quiz about the story.  The confounding variable was:

story delivery (screen or paper)

Jane investigates whether amount of sleep influences reaction time. Participants either sleep for 4 hours or 8 hours before completing a task. What is the dependent variable?

reaction time

A researcher tests whether background music affects reading comprehension. One group reads passages with music, and another reads in silence. What is the dependent variable?

Reading comprehension score

Joe studied the influence of music on nap length. Joe recruited participants and assigned them to either 1) listen to music or 2) not listen to music before taking a nap. People who listened to music gathered together to listen to the music and nap in a room at the Counseling Center. People who did not listen to music napped in their own homes. Everyone timed how long they napped. The variable that Joe intended to manipulate was:

music

Joe documented each participant's blood pressure. Joe ____ blood pressure.

measured

Joe studied the influence of music on nap length. Joe recruited participants and assigned them to either 1)listen to music or 2) not listen to music before taking a nap. People who listened to music gathered together to listen to the music and nap in a room at the Counseling Center. People who did not listen to music napped in their own homes. Everyone timed how long they napped. The confounding variable is:

the location where the participants napped

In a study examining the effects of caffeine on memory performance, what would be an example of the measure element of experimental design?

Documenting participants' memory after drinking a caffeinated drink

Which example shows a negative correlation?

As stress increases, immune system strength decreases

____ studies investigate non-causal relationships between variables

Correlational

When interpreting a correlation, it is important to remember that:

Correlation does not imply causation

In a study examining the effects of caffeine on memory performance, what would be an example of the compare element of experimental design?

Performing a statistical test to determine if caffeinated participants performed better than non-caffeinated participants

A confounding variable is a variable that:

Changes with the independent variable and affects the dependent variable