FREE ESSAY ON PSYCHOLOGY: CASE STUDY

PSYCHOLOGY: CASE STUDY

PSYC250
Case Study One
1. In Janet's final project, one of her ideas utilizes a correlational design. In a
correlational design, there is research involved. These researches usually involve using
observational, archival, or survey methods to test a hypothesis. There is at least two
variables being looked at in a correlational design, and these variables are rarely
manipulated. Instead, the variables are determined if there is a relationship between
them. In saying a relationship, we are trying to determine the similarities or
differences between the variables, and the way one variable can correlate or form a
relationship with another (Brehm, Kassin, & Fein, p. 36). 
This relationship can be measured based on the direction and strength. Let us call the
variables X and Y. When X increases and Y doesn't increase in values, we say there is no
correlation or relationship between the two variables. If as X increases, Y increases
also, we can fairly say there is a correlation or relationship between the two variables.
The relationship is either negative or positive, depending on Y increasing or decreasing
in value. If as X increases Y increases, there is positive correlation, and if as X
increases Y decreases, there is negative correlation. The strength of the correlation
indicates how strong the relationship is between the variables. The strength is
calculated using a mathematical equation, but we won't get into that in this paper. The
measurement is between -1 and +1. The closer to -1, the stronger the relationship, and
the closer to +1, the stronger the relationship. When the correlational coefficient, or
the number value associated with strength, is closer to -1, we say a strong negative
correlation. When closer to +1, we say a strong positive correlation. When it is 0, there
is no relationship (Brehm, Kassin, & Fein, pg. 36,37).
It is always important to know there is no causation or cause and effect in a
correlational design.
In Janet's first design, it is clearly a correlational design being used. Janet utilizes
two types of research methods, observation and self-report. She is observing the one
variable, facial expression and scoring it on a scale of 1-5. Negative facial expression
gets a low number and positive facial expression gets a high number. The questionnaire is
the second variable. The person who Janet observed would be given a questionnaire and
asked to rate their mood on a scale of 1-10. The lower the score, the more negative the
mood, and the higher, the more positive of a mood. 
The correlational study Janet is trying to determine is between the variable facial
expression and the other variable mood. The design is trying to form a relationship
between facial expression and mood. The criteria of this design is clearly correlational,
because of the relationship trying to be determined between the two variables, and the
fact that there is no manipulation being done. 
Next, the second research design of Janet's uses the idea of an experimental design. In
an experiment, the idea is to establish cause and effect between variables. The
experimenter does through control and random assignment. Control means that the
experimenter has control over all procedures being done. He/she has control over the
variables, the participants, and maintaining uniformity. Random assignment is that
participants have an equal chance of being exposed to the independent variable or
dependent variable. Also, participants aren't chosen for the conditions of the experiment
based on race, sex, behavioral characteristics, or personal characteristics (Brehm,
Kassin, & Fein, p. 39).
In an experiment there are two main types of variables, the independent and dependent.
The independent variable is the variable that is causation. The IV is manipulated to see
the effect. The dependent variable is the effect of the IV (Lecture, 1/24/00).
Janet's second idea is an experiment trying to prove cause and effect. The cause is the
Intro to Psychology students' mood and having to read passages about a funeral or
birthday party. The effect is their facial expression being taped as they're reading the
passages. The facial expression is being scored on the same scale as in the correlational
design. 
The independent variable is the mood of the Intro to Psychology students being measured
according to their facial expression as they're reading the different passages. The
dependent variable is their facial expression being taped and scored on a scale of 1-5. 
There is uniformity, in the fact that the participants are given either of two
conditions. The control is that the experimenter exposes the participants to the
conditions, and the equal treatment of the participants. Whether or not there is random
assignment, I don't know, it wasn't disclosed. If there isn't, this could impact the
validity of this experiment and others if not used.
2. Supposing Janet carries out her first study, which is a correlational design, Janet
would find a positive correlation or relationship between facial expression and mood.
First, Janet observes facial expression and rates it on a scale of 1-5, 1 being negative
and 5 being a positive facial expression. Second, Janet gives a questionnaire to the
participants rating their mood on a scale of 1-10, 1 being negative and 10 being
positive. If X is facial expression, and Y is mood, there would be a positive
correlation, because as X rises in value, Y rises in value also, which equals a positive
correlation. In other words, facial expressions to be scored a 1, we would expect the
mood to be low or 1 also. As facial expressions scores rise, indicating positive
expression, mood scores would rise also, indicating a positive mood. 
There is no way Janet can conclude that mood causes facial expression. In correlational
designs, there is no causation, because we don't know if X causes Y, Y causes X, or if a
third variable causes both X and Y. 
An alternative explanation for the relationship with facial expression and mood is that a
third variable that wasn't measured formed the relationship. The third variable could
have been that people just received a good deal at the mall or school cafeteria making
their mood and facial expression positive. The people that had a negative mood and facial
expression didn't receive a good deal, at the school or mall.
3. An independent variable, in my own words, is the character of interest in an
experiment that is going to be manipulated to show an effect on the dependent variable.
The independent variable is the cause in cause and effect of an experiment (Lecture,
1/24/00).
The independent variable in Janet's second study is the Intro to Psychology students.
Janet plans on manipulating the student's mood by giving half the students one passage to
read and the other half, another passage. Half of the students will get a passage about a
funeral, and the other half will get a passage about a birthday party to read.
A different way Janet could manipulate the independent variable would be to create a
control group that got no passages to read. This would give a basis to measure everything
on. This would also help in eliminating extraneous variables.
4. Janet's dependent variable in the study is the facial expressions caused by the
independent variable. Dependent variable is the effect of the independent variable. Janet
plans on measuring the dependent variable with a scale of 1-5. A negative facial
expression, probably one caused by the reading of the funeral passage, will get a low
number of 1. A positive facial expression, probably one caused by the reading of the
birthday party passage, would be scored a high number of 5. Janet is doing this by
videotaping the facial expressions as they're reading the different passages and scoring
the expressions.
A different way Janet could measure facial expressions, or the dependent variable, would
be to allow someone else to rate their facial expressions, besides Janet. This would
create less bias, so Janet's experiment could have more validity.
5. Random assignment, not random sampling, is a technique used by the experimenter to
assign participants, who are already in the experiment, to the conditions. The
participants will have an equal chance of being exposed to any of the conditions,
dependent or independent variables, as any other participant in the experiment (Brehm,
Kassin, & Fein, p. 39).
Random assignment is important in an experiment to have an equalization of the
participants chance to be exposed to the variables and conditions. By doing this, the
experimenter has greater internal validity, or the independent variable causes the
changes in the dependent variable, (cause and effect) (Brehm, Kassin, & Fein, p.40,
Lecture, 1/26/00).
6. In Janet's first study, she uses the research methods of observation and survey. There
are many advantages and disadvantages that go along with these methods. The advantage of
observation is that the observer gets a "direct measurement of behavior," (Lecture,
1/19/00). The disadvantage of observation is that observers may not know what they're
doing or observing correctly. Observing also has a disadvantage of low interrater
reliability, where different observers can't agree on their observations (Brehm, p. 31).
The advantage of the questionnaire is that you can get information on behavior that isn't
directly observable (Lecture, 1/19/00). The disadvantage of a questionnaire is that
self-esteem and self-presentations can get in the way. This can impact the way questions
are answered and many other issues. 
In Janet's second study, which is an experiment, have many advantages and disadvantages,
but here is one of each. The advantage of to an experiment is the high internal validity,
or that the indepemdent variable caused effects of the dependent variable. The
disadvantage is the low external validity, where since the experiment took place in a
controlled environment, it's hard to generalize pass that controlled environment or
general public. 
If I had to choose one of Janet's studies, I would choose the experiment. I would choose
the experiment because I like cause and effect, rather than a relationship. Experiments,
in my words, can do away with many of the confounding variables, if done right. In a
correlational design, it is harder to do away with the confounding variables, because
you're trying to form a relationship of two variables.
References
Brehm, S.S., Kassin, S. M., & Fein, S. (1999). Social Psychology (4th ed.). Boston:
Houghton Mifflin.
Bibliography
References
Brehm, S.S., Kassin, S. M., & Fein, S. (1999). Social Psychology (4th ed.). Boston:
Houghton Mifflin.