Variables. Flashcards
What are variables?
Anything that varies/changes and can be measured.
An identified event which changes in value, either within one person over ______ or between ______ in a society is known as a _______.
Time, Individuals, Variable.
Give an example of a numerical variable.
Height, weight etc.
Often variables are numerical but some variables are _______.
Categorical.
What is meant by a categorical variable?
Where values are given names, not numerical values.
Some variables such as height are easy to ______.
Measure.
Give an example of a variable that may be more difficult to measure directly.
Anxiety.
In psychology, what do we treat concepts like intelligence, anxiety or attitude as?
As Hypothetical Constructs.
What is a hypothetical construct?
A Hypothetical Construct is assumed to exist as a factor which explains observable phenomena. Eg. did well on task because they are intelligent.
Although we can see the physical signs of anxiety, what is it hard to do?
Its hard to actually measure anxiety.
In order to measure anxiety, we need to do so indirectly, so what must we do?
Set up an Operational Definition of anxiety.
What does an Operational Definition do?
It states how we are going to measure a variable.
In setting up an Operational definition of anxiety, what measurements may be used?
- Self report eg. questionnaire
- Physiological Measure eg. sweat on hands
- Observation eg. tick off signs against list of criteria.
What is an Operational Definition?
An operational definition of an event or phenomenon is when something is defined in terms of the procedures required to measure it.
In , we need to state the definition of the variable in exact terms of how we are going to measure it. What is this known as?
An Operational Definition.
What will a good Operational Definition allow?
- To agree or compare with others’ measurements
- To allow replication of the experiment.
The measurement of a variable must be ______ in an experiment.
Systematic.
When can an operational definition not measure all aspects of a phenomena?
When measuring hypothetical constructs eg. intelligence/ anxiety.
What can give us a reasonably valid method of measuring some part of a hypothetical construct?
An Operational Definition.
We need an Operational Definition to state exactly what we are counting as a _____ of the construct.
Measure.
What is the essence of scientific research (in terms of variables)?
To relate changes in one variable to changes in another variable.
Variables are the basis of ___________.
Experimentation.
Why do we need to have effective selection and manipulation of variables?
In order to be able to make confident assertions about the results.
In experiments psychologists ask about the _____ between variables.
Relationship.
What do psychologists investigate (in terms of variables)?
The effect of one variable upon another.
What are the two types of variables?
Independent Variables and Dependent Variables.
What is the independent variable?
The variable that causes the changes observed by the experimenter.
Define what is meant by Dependent Variable.
The dependent variable is affected by the independent variable.
The ____ variable is the thing that we change, whereas the ______ variable is the thing we measure (as a result of the change).
Independent, Dependent.
What is the Fundamental Process of scientific research?
To relate the Independent Variable to the dependent variable,holding all other relevant variables constant while the Independent Variable Changes.
What do we start off an experiment with?
A prediction (hypothesis) that changing the IV will have a particular effect on the DV.
If the dependent variable is affected by the independent variable, what is the experiment said to be?
A Success.
If there are 2 different values for the IV (eg. Learning by rehearsal or learning by imagery- both come under the mode of learning), what is this known as?
The Levels of the IV.
Identify the IV and DV in the following example:
-The influence of music (present or not) on productivity rates in an office.
IV= Presence/Absence of music (levels of IV) DV = Productivity rates.
What is an Extraneous Variable?
Any Variable other than the IV which might have an effect on the DV measured.
What variables must we control in order to make a confident assertion that it was the IV that affected the DV?
We must control the extraneous variables by keeping them constant.
In order for a reliable experiment, we must keep the extraneous variables _____ throughout the experiment.
Constant.
If the effects of extraneous variables are not controlled, what can we not state?
We cannot state that it was the changes in the IV that affected the DV.
______ variables- is when extraneous variables influence confounds(confuses) the proper interpretation of the results.
Confounding.
We tend to think of _____ variables in advance when setting up and experiment.
Confounding.
What is an extraneous variable isn’t controlled and impacts the results what could we call this?
A confounding variable.
Name this-
A variable other than the IV which might have an affect on the DV.
An Extraneous Variable.
To compare conditions fairly we want to control the effects of all ______ variables apart from the __________.
Extraneous, Independent Variable .
In an experiment we must eliminate any potential ___________.
Confounds.
In some cases an extraneous variable could operate in what manner? (eg. may get better at task due to practice) What must be done?
A systematic Manner.
Experiment should be designed to remove the systematic effect.
