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

The technique of placing comparable subjects in all experimental groups in an attempt to control tor confounding variables is called ____.

Random assignment is feasible only when an investigator is using a manipulative experimental strategy to "create" values on an independent variable.

When an experimental research strategy is used,inferences of causation can be made only when confounded variables are controlled.

What is a confounding variable and how can they be controlled?

Once subjects have been selected they should be ____________________to groups.

Statisticians may determine the effects of violating assumptions by

Twenty alcoholics are given a test to measure anxiety before and after a one-month detox program.The appropriate design for testing the significance of the difference between the two group means is a

Random assignment is feasible only when an investigator is using an _____ strategy to "create" values on a(n)_____ variable.

A Monte Carlo study is a computer simulation study in which the statistician uses the computer to generate scores for hypothetical populations that he or she knows violates a distributional assumption in some way.

Based on the Applications to the Analysis of Social Problems section of Chapter 9,historical variables that are confounded with age refer to

An investigator was interested in determining if the size of a coin influenced judgments of numerosity when people were asked to make judgments of how many coins were in a pile of coins.Fifteen subjects were asked to estimate the number of pennies in a display of 43 coins.In another condition,15 different subjects estimated the number of dimes for the same display.The value of the coin would be classified as a ____ variable.

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).In Dr.Len's study what are some disadvantages with using this particular design?

One disadvantage of using a within-subjects design is carry-over effects from condition to the next.

The _____ design can offer considerably more experimental control over individual difference variables than the _____ design.

A ____ variable is related to the independent variable in a manner that renders interpretation of the relationship between the dependent variable and independent variable ambiguous.

The robustness of statistical test is determined by sample size only.

Dr.Nan is studying the effects of Ginseng on recall.He has 2 groups of subjects, (20 subjects in each group).Subjects are given Ginseng or Placebo and then asked to recall a list of words they previously studied.However,to avoid confounds what should Dr.Nan do?

What is matching?

In contrast to an experimental strategy,an observational strategy or a non-experimental strategy involves the process of actively creating values on an independent variable for the research participants.

It is possible that 2 variables can appear to be related to each other but there is no causal relationship.