Exam 9: Principles of Research Design and Statistical Preliminaries for Analyzing Bivariate Relationships

Which of the following methods can be used in the design of a study to control for alternative explanations of the results?

The within-subjects design can offer considerably more experimental control than the between-subjects design.

A disturbance variable increases sampling error by increasing variability within groups.

Random assignment is an effective method for controlling confounding variables defined by individual differences.

Dr.Chin is studying the effect of lysine on memory.He gives one group lysine and the other subjects a placebo.He is using a____________________.

_____ statistics tend to focus on medians,interquartile ranges,and ordinal level measures.

If a confounding variable has been included in the design of an experiment,then interpretation of the results would be ___.

Describe how random assignment helps to control for alternative explanations.

With the technique of matching,an individual in one group is "matched" with an individual in each of the other groups such that all of these individuals have the same value on the independent variable.

A matched-subjects design often has the power of a within-subjects design while avoiding the problem(s)of ___.

A method that may minimizes the possibility of confounding due to individual differences is ____.

A ____________________is a variable that is related to the independent variable and may affect the dependent variable if it is not controlled for.

Dr.Len wants to determine whether or not dextrin causes people to lose weight.He gives 10 subjects dextrin and 10 subjects a placebo.He measures their weight every day (since weight seems to fluctuate daily)until the experiment is discontinued (after 4 weeks).What type of design is Dr.Len implementing?

A disturbance variable is one that is related to the independent variable (and hence,confounded with it)but that also affects the dependent variable.

Comparing how well males and females perform on a video game that simulates landing a space shuttle is _____.

If a researcher administers either 0 mg,10 mg,or 20 mg of a drug to subjects in an experiment,then the group of subjects receiving the 0 mg treatment is best thought of as a(n)____.

Distinguish between parametric and nonparametric statistics.

A confounding variable

If you are measure how satisfied they are with their marriage you may want to ____________________couples on the amount of time they've been married.

Since experimental independent variables will always be confounded with all other variables that are naturally related to them,causal inferences are typically not possible when an experimental research strategy is used.