Chapter 4 (2)

Question 1

An _____ _____ observes individuals and measures variables of interest but does not attempt to influence the responses

Answer 1

Observational study

Question 2

An ______ deliberately imposes some treatment on individuals to measure their responses

Answer 2

Experiment

Question 3

When our goal is to understand cause and effect, ____ are the only source of fully convincing data

Answer 3

Experiments

Question 4

A ______ _______ is a variable that is not among the explanatory or response variables in a study but that may influence the response variables

Answer 4

Lurking variables

Question 5

_______ is when the effects of two variables on the response variable can not be separated from each other

Answer 5

Confounding

Question 6

A specific condition applied to the individuals in an experiment is called a ______

Answer 6

Treatment

Question 7

The _______ _____ are the smaller collection of individuals to which treatments are applied

Answer 7

Experimental units

Question 8

When experimental units are human beings, they are often called _____

Answer 8

Subjects

Question 9

The explanatory variables in an experiment are called ____

Answer 9

Factors

Question 10

Badly designed experiments often yield worthless results because of ______

Answer 10

Confounding

Question 11

Most well-designed experiments compare two or more ______

Answer 11

Treatments

Question 12

_____ _________ means that experimental units are assigned to treatments at random, using some sort of chance process

Answer 12

Random assignment

Question 13

The primary purpose of a ___ ____ is to provide a baseline for comparing the effects of the other treatments

Answer 13

Control group

Question 14

The three basic principles of experimental design are _____, ___ ______, and ________

Answer 14

Control, random assignment, replication

Question 15

_____ lurking variables that might affect the response

Answer 15

Control

Question 16

______ _______ uses impersonal chance to assign experimental units to treatments

Answer 16

Random assignment

Question 17

______ uses enough experimental units in each group that differences in the effects of treatments can be distinguished from chance differences

Answer 17

Replication

Question 18

Response to a dummy treatment, usually a psychological effect is called the ___ ____

Answer 18

Placebo effect

Question 19

In a ____-____ experiment, neither the subjects nor those who interact with them and measure the response variable know which treatment a subject received

Answer 19

Double- blind

Question 20

An observational fact so large that is would rarely occur by chance is called ______ _______

Answer 20

Statistically significant

Question 21

A second form of control is to form ____ of individuals that are similar in some way important to the response

Answer 21

Blocks

Question 22

________ ____ is a separate form of blocking for compared just two treatments

Answer 22

Matched pairs