Chapter 4 - Research Design Fundamentals

Variable

Term used to describe anything (event, situation, behavior, individual characteristic) that can take on more than one value

Level of a variable

Term used to describe the exact value of a variable

Situational variables

Characteristics of a situation/environment within a study

Response Variables

Measured behavioral responses of individuals in a study

Participant Variables

Characteristics of individuals brought with them into the study

Independent

Manipulated variables of interest within an experiment

Dependent Variable

Measured variables of interest in an experiment

Dependent Variable

Outside variables within an experiment that must be controlled as they may effect the dependent variable

Confounding Variables

Uncontrolled extraneous variables that co-vary with independent variables

Mediating Variables

Variables that explain a causal relationship between two variables, they are often psychological in nature

1. Procedures used to change it

2. Method used to measure it

An operational definition is a variable that is defined in terms of either:

empirical, replicable

The main goal of using an operational definition is to make research __________ and _________

Procedures to produce/change variable

“Fear is exposure to 1000 sticks of dynamite detonated 100 yards away from participant”.

Which of the 2 ways to create an operational definition for a variable is presented here?

Methods used to measure variable

“Dreaming is the amount of REM sleep displayed during the night”

Which of the 2 ways to create an operational definition for a variable is presented here?

Operational Definition

An _________________________ defines a variable either in terms of procedures to produce or method used to measure.

Non-Experimental

In ___________________ methods, all variables are measured; none are manipulated

Non-Experimental methods can establish correlation between variables. They cannot establish causation

What can Non-Experimental Methods establish? What are they unable to establush?

Non-Experimental Method

Correlational research and quasi-experiments are which type of research method?

Causation

With proper experimental control, experimental methods can establish _________

Due to the lack of control, cannot rule out alternative explanations

If variables are measured together, temporal precedence may not be known

Regarding the 3 ways to establish causation, where do Non-Experimental Methods fall short

Hint: The 3 ways are

1. Co-variation

2. Temporal Precedence

3. Rule out alternative explanations

Experimental

In _____________ methods, atleast one variable is manipulated while the other is measured.

Random Assignment

Method of experimental control that is often used for ruling out participant variables

Constancy across conditions

Method of experimental control that may be used to rule out situational variables

Quasi-experiment designs

Experiment design that resembles experiments, but often due to ethical reasons cannot have full experimental control (e.g., studying trauma in children)

Internal Validity

Refers to the ability to state whether cause-effect relation exists in a study

External Validity

Refers to how well results of a study can be generalized; applicable to the real world

C effects both variables

In a correlation study with variable A and variable B, how might a third variable effect the study?

C may be the cause of the effect of B. No effect on A

In an experimental study with variable A and variable B, how might a confounding variable effect the study?

Positive/Direct

As values of one variable increase, values of other increase as well

Linear

Points tend to fall along a straight line

Monotonic

Term to describe when a relationship is in one direction

Negative

As values of one variable increase, values of other decrease

Curvilinear

Term to describe when the correlational line is not straight, it is curved

Non-monotonic

Term to describe when a correlational line reverses in direction at different points of graph