Exam 7: The Experimental Research Strategy

In New York State,the winter months produce higher heating bills and higher levels of depression.Although the numbers show that higher heating bills are related to higher levels of depression,which of the following is the most likely explanation for this relationship?

In an experiment,any variable that varies systematically with the treatment conditions and might influence the participants' scores is called a _____________ variable.

Dr.Kim varies the amount of caffeine given to three groups of participants (0,100,and 200 mg)and then observes the anxiety level for each group.The 0-mg condition represents the

The purpose of an experiment is to demonstrate that changes in one variable are responsible for causing changes in a second variable.

Dr.Adams is studying how the quality of breakfast influences academic performance for elementary school children.A sample of 100 children is selected.Fifty children are provided with a nutritious breakfast when they arrive at school each morning.The other 50 children are given a doughnut each morning.After three months,Dr.Adams records the academic achievement level for each child and compares the two groups of scores.In this example,how many levels are there for the independent variable?

If two variables are consistently related to one another,you can conclude that changes in one variable are causing changes to occur in the other.

The specific treatment conditions that are used in an experiment are called the

A researcher has observed that people who suffer from an eating disorder tend to have lower self-esteem than people without a disorder.However,the researcher is not sure whether the lower self-esteem leads to an eating disorder or whether having an eating disorder leads to lower self-esteem.This is an example of

What is the advantage of a field study over a laboratory study?

Randomizing a variable such as participant gender guarantees that it will not become a confounding variable.

Results from a research study indicate that athletes who were given an electrolyte drink had better endurance scores on a treadmill task than athletes who were given water.For this study,the independent variable is water versus electrolyte drink.

Dr.Jones systematically varies the temperature in the laboratory (70,80,and 90 degrees)while holding other variables constant,and observes that the participants' activity level decreases as the temperature increases.This illustrates

In order to establish an unambiguous cause-and-effect relationship between two variables,it is necessary to eliminate the possible influence of extraneous variables.

Which of the following is the primary goal for randomizing an extraneous variable in an experiment?

The measured variable in an experiment is the

In an experiment examining how alcohol influences men's judgments of female attractiveness,one group of participants is given non-alcoholic beer before they make their judgments.This would be classified as a placebo control condition.

In order to establish an unambiguous relationship between two variables,it is necessary to eliminate the possible influence of

Dr.Jones 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.Jones 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.Jones measures the level of depression for the people living in the houses.In this example,the level of depression is the ________ variable.

What is the advantage of a laboratory study over a field study?

An experiment comparing a treatment group with a no-treatment control group has no independent variable.