Research Methods

Let's take a look at real science!!!!

There are two reasons why it is vital that you have a solid understanding of research methods.  First, you are more likely to see a free response question on the AP exam from this topic than anywhere else.  Second, above all, it is important to remember that psychology is a science.  So whenever a psychologist has an idea that he or she wants to show the world, there are a certain set of rules they must follow called the scientific method.  The Scientific method is a body of techniques for investigating phenomena and acquiring new knowledge, as well as for correcting and integrating previous knowledge.

Hopefully, every theory and idea that you have learned about so far in this course (in all of your science classes for that matter) has been tested through the scientific method.  There are basically two types of research that can take place; applied and basic.  Applied research is when the scientist has clear and practical reasons and applications for her study.  If a psychologist was trying to come up with a new behavior therapy to stop heroin use, it would be applied research. 

Basic research explores questions that are really interesting to psychologists but have no immediate, real-world application.  Studying the differences between cultures and physical beauty is an example of basic research.

Now before we go on to the various ways to conduct research it is important to know that all research should be both valid and reliable (hope you remember these terms).  Research is valid when it measures what the researcher sets out to measure; is it accurate.  Research is reliable when it can be replicated.  This is an important idea.  If I conduct a research study and discover that AP Psychology teachers are consistently the best looking teachers in high schools, would everyone automatically believe me?  I hope not.  After I publish my results and how I conducted the research, I hope that other scientists try to copy my experiment.  If all the scientists around the world replicate my study and come up with similar results, then the research is reliable and we can start putting it in our text books.  ALL TOO OFTEN we hear about some research (either a new drug or fact about food etc...) and we take the information as fact.  It usually has only been done once!!!!  You should not rely on any research until it has been replicated over and over again.

Now most research has an hypothesis.  I know that in middle school you learned that a hypothesis was "an educated guess", and that is kinda right.  A hypothesis really is a way to express a relationship between two variables.   Let's say I notice that AP Psychology teachers are incredibley good looking, so I set out to explore the relationship between attractiveness (one variable) and AP Psychology teachers (another variable).  There are many ways to delve into the relationship using the scientific method (and some ways are alot better than others).  For the rest of this unit we will explore different ways we can talk about conducting research and finish up with some ways we can describe the results of the research we do to others.

Descriptive Research

Descriptive research is any type of research that describes the "who, what, when, where" of a situation, not what caused it.  It describes a situation, but in the end, tells us nothing about how the universe works.

A classic example of descriptive research is a case study.  A case study is a research method used to get a full, detailed picture of one subject or a small group of subjects.  For example, if I wanted to study anorexia and its link to drug use (not there is one) and I chose to study Nicole Richie.

 

So I follow Nicole around.  I study her every move.  I interview her.  I talk to her friends (maybe Paris, maybe not...).  I research her childhood.  I get a complete picture of Nicole Richie.  I learn all about her life.   It would be a very interesting story (a detailed version of those VH1 specials).  This would be a case study.

BUT there are a few very big problems with the case study.  FIRST, I may learn all about her alleged anorexia and drug use (the what, how, where and when) but her story would never truly tell me the reason WHY.  I would never be able to say with certainty that the link between anorexia and drugs is.......

The SECOND and maybe more significant weakness of a case study is that the results are not generalizable to the rest of the population.  What that means is that studying Nicole would not give me any idea why millions of people become anorexic and use drugs.  Studying just ONE person is not going to tell me anything about the many more out there.  I must study a larger sample of people.  Besides, is Nicole Richie a typical anorexic?  No way, she is the daughter of a Commodore (Lionel) and the best friend (or arch enemy) or my one true love Paris Hilton.  Studying Nicole would tell me nothing about the average anorexic, drug using girl.

We constantly make the mistake of taking a single case study and making policy changes based on that one example.  Take Columbine for example.  A horrible shooting occurred in a Colorado school and is was studied every which way by the popular media and scientists.  Columbine became a case study for school violence.  What happened was high schools around the country began making changes to their security policies because of the fear that another Columbine would occur.  In reality, do you think your school was any more or less dangerous before or after Columbine?  Probably not.  But the fear of the case study of Columbine was the catalyst for unnecessary policy changes around the country.  Case studies can be both powerful and dangerous.

Other types of research can also be descriptive research.  For example, it is possible that surveys or naturalistic observation can be designed just to gather descriptive data.  But for the sake of simplicity we will define them under their more common guise of correlational research.

Correlational Research

There are many types of correlational research.  The commonality among all types of correlational research is that they explore relationships between variables.  Where descriptive research only described what was going on, correlational research talks about the link between different things.  It is important to understand that correlational research does NOT tell us that variable A caused Variable B, but rather that they are somehow related.

For example, if I told you that there was a correlation between domestic violence (violence between a family members) and bowling you would look at me strangely.  But there is a relationship between the variables (variable 1- domestic violence, and variable 2- bowling).  As more people bowl in the US, more domestic violence occurs. 

Does that mean that bowling causes domestic violence- like you had bad game and take it out on a loved one.  Or domestic violence causes bowling- like you fight with a sibling and feel the need to take it out on some pins.  As you have already guessed- one does not cause the other to occur, but they are related- for every time people bowl, I can predict that domestic violence will go up, and every time domestic violence goes down I should be able to find a lane at the local bowling alley.  There is a hidden variable that links both of them together.  In this case it is winter time.  In the winter more people bowl and more people stay in their homes (which increases the chances of domestic violence).

Direction of a Correlation

Before we examine the different types of correlational research methods, understand that correlations can go in two directions; positive and negative.

Correlational Coefficient

Scientists measure the strength of a correlation by using a number called a correlational coefficient.  Now you do not have to know how they get the number, but you should know what it means when you see it.  The number range from -1 to +1.  If two variables (like studying and grades) have a correlation above zero (like +.76) then you have a positive correlation and the more you study, the better grades you have.  The the number is below zero (like -.42) then you have a negative correlation and when one variable goes up the other goes down (like garlic and dating).  If two variables have a correlation of zero then they have NO relationship with each other.  The closer the numbers go to either +1 or -1, the stronger the correlation.  The strength has nothing to do with whether the number is positive of negative.  A correlation of -.88 is stronger than one that is +.56.  the closer the number gets to zero (whether positive or negative), the weaker the correlation.

Types of Correlational Studies

There are many different ways to show a correlation between two variables.  Let's discuss some of the more popular ways; the survey method and naturalistic observation.

The Survey Method

Perhaps the most common type of research around is survey research.  Every time you receive a letter in the mail asking you to take a minute and answer a few questions, or get a phone call begging for ten minutes of your time to speak about how you feel about ??????, you are experiencing the survey method of research.  All surveys have one thing in common, they ask questions. 

Now there are good and bad things about surveys in research.  The good- no matter how you do it, internet, mail, phone, in person- they are fairly cheap.  You can cover large populations of people easily if you use the phone or internet.  The bad aspects of surveys is that 1. the response rate is REALLY low (for every 100 mailing you send out, you will be lucky to get one back).  Second, people can lie on the survey so you can always question the validity of your data.

Let's break down the survey method as a tool of correlational study.  Pretend our hypothesis was the more garlic people eat, the less they date.  First, we have to come up with some survey questions (pretend they ask about the amount of garlic one has eaten in the past 6 months and how much they have dated in the past sixth months).  Hopefully, when people answer the survey, we will see that people who have stated that they have eaten a lot of garlic have also answered that they have dated less (a negative correlation).

But who are we going to give the survey to?  As with ALL types of studies (except some case studies) we must choose a sample of people to take the survey (a sample is just a group of subjects).  We have to first identify a population of people from which we are going to get the sample.  The population includes anyone who can possibly be chosen to be part of the sample.  If we are studying anorexic women and their dating habits we would choose a sample from a population of anorexic women (asking a chubby dude like me would not make sense for an anorexic study so I would NOT be a part of the population).  In the case of garlic and dating, I am going to limit my population to single men and women between the ages of 18-25 from the New Braunfels area (if I do not limit my population, then I would have to start contacting people from all around the world).

Now, how do I pick people to be a part of my sample.  Do I call all my single buddies in the New Braunfels area and give them the survey?  That would not be a very fair way of doing it.  To make the survey valid I MUST randomly select a sample from the population.  Random selection means that every person in my population has an equal chance of being selected for the survey.  If I can do this, then my sample has a greatly likelihood of actually representing the larger population I am studying.  How do I randomly sample my population- I can randomly pick names out of a phonebook (but in a way that is unfair to single people in New Braunfels who do not have phones)- in other words, finding a truly random sample is not easy.

Naturalistic Observation

Another correlational research method is called naturalistic observation (although you can also use it as a descriptive research tool as well).  Naturalistic observation is when a researcher attempts to observe their subjects in their natural habitats without interacting with them at all.  Pretend I had a hypothesis; marijuana increases hunger (munchies).  If I wanted to use naturalistic observation I would find a bunch of pot users and watch them.  I would follow them around to parties, watch them smoke, and then see if they eat. 

Experimental Method

The best method of answering cause and effect questions.  Used whenever possible because they allow psychologists to control experience of subjects and draw conclusions about cause and effect.

Variables- things that can assume more than one value
Independent (IV) condition in a study that is manipulated so its effects may be observed
Dependent (DV) a measure of an assumed affect of an IV
Ex. Does a ritalin lessen ADHD? IV-ritalin    DV-ADHD
Extraneous (EV) conditions experimenter wishes to prevent from affecting the outcome of experiment

Experimental and Control Groups
Experimental- group whose members receive the treatment
Control- do not receive treatment, while other conditions are held constant. Will receive the placebo, which is given to help rid confounding variable of expectation.

Blind Experiments
Single-blind- patient does not know if they are receving treatment or placebo

               
Double-blind- neither examiner or patient know who is receiving the placebo.  All FDA studies require double-blind