Psychology for Dummies Read Online Free PDF Page A

well-known personalities in the field. Other knowledge is based on clinical experience without any systematic investigation. Finally, a good-sized chunk of information that’s out there is purely theoretical, but it makes sense on rational/logical grounds.
    The vast majority of psychologists prefer to use the scientific method when seeking truth because it’s seen as a fair and impartial process. When I do a research study, I’m expected to outline exactly what I’m doing and what it is that I claim to be looking for. That way, if people want to try to prove me wrong, they can repeat my work, step by step, and see if they get the same results. If knowledge is based on authority alone, I can never be sure that the information I receive is unbiased and trustworthy. When the scientific method is in place, a theory that doesn’t match the empirical results “experienced” in a research study is labeled inaccurate. Time for a new theory! Scientists should never change their experimental data to match their original theory — that’s cheating!

Developing a Good Theory
    Because a fair amount of psychological knowledge is based on theory, it may by helpful to know what a theory is exactly. If you already have a handle on what a theory is, indulge me for a moment. A
theory
is a set of related statements about a set of objects or events (the ones being studied) that explains how these objects or events are related.
    Theories and hypotheses are similar but not exactly the same thing. Psycho-logists test theories by studying their logical implications. Hypotheses are specific predictions based on these implications. We can add new information to theories, and we can use existing theories to generate new ones.
     

     
    Not every theory is a good theory. In order for a theory to be good, it must meet three criteria:
    Parsimony: It must be the simplest explanation possible that still explains the available observation.
    Precision: It must make precise, not overly large or vague, statements about reality.
    Testability: It must lend itself to scientific investigation.

Researching for the Truth
    Psychologists use two broad categories of research when they want to scientifically evaluate a theory:
    Descriptive research: Consists of observation and the collection of data without trying to manipulate any of the conditions or circumstances being observed. It’s a passive observation of the topics being investigated. Descriptive studies are good for developing new theories and hypotheses and are often the first step for a researcher investigating things that haven’t been studied much. However, they don’t help much if you’re interested in cause and effect relationships.
    If I’m only interested in the content of bus-stop conversations, I may videotape people talking to each other at a bus stop and analyze the video. But, if I want to know what causes people to talk about certain subjects at bus stops, I should conduct an experiment.
    Experimental research: Involves the control and manipulation of the objects and events being investigated in order to get a better idea of the cause and effect relationships between the objects or events.
    Say I have a theory of bus-stop conversations called the “five-minute or more rule” that states, “Strangers will engage in conversation with each other only after having been in each other’s presence for five or more minutes.” My hypothesis would be, “After five minutes, apparent strangers will engage in a conversation beyond the simple pleasantries and greetings afforded to strangers.” That is, I am hypothesizing that once strangers at a bus stop have been there for five minutes, they will start having a conversation. How can I test my hypothesis?
    I could just hang out at a bus stop and watch to see if it happens. But how could I know that my five-minute-or-more rule is behind my observations? I couldn’t! It could be any number of things. This is a problematic issue in research I