Making Sense of What People Do: Psychology Essentials - Getting Started with Psychology

Psychology For Dummies - Adam Cash 2013

Making Sense of What People Do: Psychology Essentials
Getting Started with Psychology

In This Chapter

Image Figuring ourselves out

Image Using a little folk psychology

Image Clearing things up

Image Understanding the placebo effect

In a way, each of us is an amateur psychologist of sorts. Professional psychologists aren’t the only ones who try to figure people out. When I started taking psychology courses, I had my own ideas about people. Sometimes I agreed with the theories of Freud and others, and sometimes I disagreed wholeheartedly. I’m not alone. Most people seem to have specific ideas about what makes others tick.

Psychology covers a topic we all have experience with — people. It’s pretty hard to say the same thing about chemistry, astronomy, or electrical engineering. Of course, we all encounter chemicals every day, but I can’t remember the last time I asked, “How do they get that mouthwash to taste like mint?” However, a psychologist may ask, “What happens inside a person so that her toothpaste tastes like mint?”

One of the best places to catch armchair psychologists (people who speculate without systematic evidence) in action is the local coffeehouse or watering hole. People love talking about the whys and the wherefores of other people’s behavior. “And then I said. . . .” “You should have told him. . . .” Hanging out in public social spaces is much like being in group therapy sometimes. People work hard at figuring out other people.

Image Psychologists sometimes call this armchair psychologizing folk psychology — a framework of principles used by ordinary people to understand, explain, and predict their own and other people’s behavior and mental states. In practice, everyone uses a variety of psychological notions or concepts to explain individuals’ mental states, personalities, and behaviors. Two concepts in particular that people tend to rely on are beliefs and desires. That is, most people assume that people have beliefs and that they act on those beliefs. So when you wonder why people do what they do, it’s easy; it’s because of their beliefs.

Yet folk psychology isn’t the only tool in the bag of an armchair psychologist. People also explain other’s behavior in terms of luck, curses, blessings, karma, fate, destiny, and other non-psychological terms. Using these explanations isn’t necessarily a bad thing. It’s pretty hard to explain from a psychological perspective why someone wins the lottery. Explaining why someone continues to buy tickets when they keep losing, however, is a question for psychology.

In this chapter, you find out how psychologists go about their business, including how overarching theories frame the questions they ask and the variables they look at. You also get a look at the various branches of psychology that include more than what people typically think of such as clinical psychology. Finally, you see how the discipline of psychology works to be as scientific as possible by basing its knowledge on research and statistical methods, which shores up its credibility among the other scholarly disciplines.

Finding a Framework

At a very basic level, psychology is a branch of knowledge. Psychology exists among and interacts with other scientific and scholarly disciplines in a community-like environment of knowledge, and contributes a vast collection of theories and research to help answer questions related to human behavior and mental processes. A number of other fields of study — physics, biology, chemistry, history, economics, political science, sociology, medicine, and anthropology — attempt to use their own perspectives to answer the same basic questions about people that psychology addresses.

One comment I get from students from time to time is, “What makes you think that psychology has all the answers?” My answer is, “Psychologists are just trying to provide a piece of the puzzle, not all the answers.”

To enable psychology to contribute to the community of knowledge about people, over the years, psychologists as a group have come up with a basic set of broad theoretical perspectives, or frameworks to guide the work of psychology. These broad theoretical frameworks are sometimes referred to as metatheories. The lion’s share of psychological research is based on one or more of these broad frameworks or metatheories.

Each metatheory provides an overarching framework for conducting psychological research and comes with a different point of emphasis to figure out what people do, and why and how they do it. Other perspectives represent hybridized approaches, such as motivational science and affective neuroscience. But for now, I’m just sticking with the basics.

In this section, I describe the most common metatheories psychologists use when they find a behavior or mental process they’re interested in researching. Work typically begins from within one of these theories.


The biological approach centers on the biological underpinnings of behavior, including the effects of evolution and genetics. The premise is that behavior and mental processes can be explained by understanding genetics, human physiology, and anatomy. Biological psychologists focus mostly on the brain and the nervous system. (For more on biological psychology, see Chapter 3.) Neuropsychology and the study of the brain, genetics, and evolutionary psychology are included within the biological metatheory.

For an example of biology’s impact on behavior, just think about how differently people act when they’re under the influence of alcohol. Holiday office parties are good laboratories for applying the biological perspective. You walk into the party and see Bob, the relatively quiet guy from accounting, burning up the cubicles. Bob’s transformed into a lady’s man. He’s funny. He’s drunk. Do you think Bob will remember?


The psychoanalytic/psychodynamic metatheory emphasizes the importance of unconscious mental processes, early child development, personality, the self, attachment patterns, and relationships. This approach explores how these mental and developmental processes interact with the challenges of life and everyday demands to affect the person you are and how you behave.

Sigmund Freud founded psychoanalysis in the early 1900s; since then, hundreds of theorists have added to his work. The later theories are typically labeled psychodynamic because they emphasize the dynamic interplay between various components of mind, the self, personality, others, and reality. Object Relations Theory and Self Psychology are two specific theoretical perspectives that fall within the psychoanalytic/psychodynamic metatheory. (For more on psychoanalysis/psychodynamics, flip to Chapters 9 and 15.)


Behaviorism emphasizes the role and influence of a person’s environment and previous learning experiences to understanding behavior. Behaviorists don’t traditionally focus on mental processes per se because they believe that mental processes are too difficult to observe and measure objectively. In the framework of behaviorism, the “why” of behavior can be explained by looking at the circumstances in which it occurs and the consequences surrounding someone’s actions. Classical conditioning and operant conditioning are ways of understanding behavior and they lead to behavior modification, a specific approach to modifying behavior, and helping people change that comes from the metatheory of behaviorism (see Chapter 8 for details on some behavior-modification techniques that are based on classical and operant conditioning).


The cognitive framework centers on the mental processing of information, including the specific functions of attention, concentration, reasoning, problem solving, and memory. Cognitive psychologists are interested in the mental plans and thoughts that guide and cause behavior and affect how people feel. Intelligence testing and information-processing theories are examples that fall within the cognitive metatheory.

Whenever someone tells you to look at the bright side, they’re coming from a cognitive perspective. When something bad happens, most people feel better if the problem gets solved or the issue is resolved. But how should you feel if nothing changes? If circumstances don’t change, do you have to feel bad forever? Of course not; in most cases, people can change the way they think about a situation. You can choose to look on the bright side — or at least not look solely at the downside. That’s the gist of cognitive therapy.

Humanistic and existential

The humanistic and existential metatheory emphasizes that each person is unique and that humans have the ability and responsibility to make choices in their lives. I’m not a victim of circumstance! I have choices in my life. Humanists believe that a person’s free choice, free will, and understanding of the meaning of events in his or her life are the most important things to study in order to understand behavior. The works of Victor Frankl, Rollo May, and Fritz Perls and the study of spirituality and religion are examples that fall within this framework.

In your own life, have you ever felt like just another nameless face in the crowd? Has your life ever seemed as if it’s controlled by the winds of chance? How did it feel? Probably not very good. Feeling like you have choices — and making good choices — gives you a sense of true being and affirms your existence. That’s the case with most people anyway, and psychologists who work within the humanistic and existential metatheory believe that behavior is simply a result of choice.


The sociocultural approach focuses on the social and cultural factors that affect behavior. This is all about the enormous power of groups and culture on the why, how, and what of behavior and mental processes.

Tattoos and body piercings are good examples of this power. At one point in mainstream culture, people who got ink and piercings were perceived to be acting outside of the status quo, so “status quo” people weren’t lined up outside the tattoo or piercing parlor. Nowadays, both are widely accepted, and even Mr. Status Quo may have a tat or piercing (or two or three).

Social and cross-cultural psychology fall within the sociocultural metatheory.


Feminist psychology focuses on the political, economic, and social rights of women and how these forces influence the behavior of both men and women. Although feminism had some earlier influence, the feminist perspective in psychology gained momentum during the women’s movement of the 1960s.

One issue in particular that has caught the attention of feminist researchers and clinicians is eating disorders. From the perspective of feminists, eating disorders are largely the consequence of excessive pressures to be thin that mass media and culture place upon females of all ages. Feminists draw attention to the fashion magazines and female role models in popular culture.


The Postmodern metatheory questions the very core of psychological science, challenging its approach to truth and its focus on the individual. Postmodernists propose, for example, that in order to understand human thinking and reason, we need to look at the social and communal processes involved in thinking and reason. Reality is not something out there independently; it is something that humans, as a community, create.

Postmodernists make the argument that people in powerful positions have too much to say about what is “real” and “true” in psychology, and they advocate a social constructionist view of reality, which states that the concepts of “reality” and “truth” are defined, or constructed, by society. These concepts, according to this framework, have no meaning apart from the meanings that society and its experts assign to them. Narrative and constructionist theories are examples that fall within the metatheory of Postmodernism.

Working with the Biopsychosocial Model

Over the years, each of these metatheories has enjoyed its day in the sun, only to be put on the shelf when the next big thing came along. This revolving door of explanatory frameworks makes it tough to sort through the different metatheories and choose the best one for finding the answers you’re seeking. Where do you begin?

One alternative to picking a metatheory is to combine several views together, thus adopting an integrationist approach. The biopsychosocial model of psychology represents a popular attempt at integration.

The basic idea behind this model is that human behavior and mental processes are the products of biological, psychological, and social influences. Biopsychosocialists try to find out how these influences interact to produce behavior. They believe that any explanation of behavior and mental processes that doesn’t consider all three primary factors (body, mind, and environment) is incomplete.

Feeling out the role of the body

As material beings, humans are made of flesh and bones. Any discussion of thoughts, feelings, and other psychological concepts that doesn’t factor in biological makeup and function, especially the brain and nervous system, ignores the fundamental facts of human existence.

Take the mind for example. Most people agree that they have a mind and that others (well, most others) have one too. But where does this mind exist? Psychologists accept that the mind exists in, or is synonymous with, the brain. The biological metatheory is integrated into the biopsychosocial model because of this component. You may say that, just as digestion is what the stomach does, “mind” is what the brain does.

Thinking about the role of the mind

When most people think about psychology, they have this aspect of the biopsychosocial model in mind (no pun intended). Thoughts, feelings, desires, beliefs, and numerous other mental concepts are addressed by the biopsychosocial model through analysis of the role of the mind.

What if this book was about botany? Would the biopsychosocial model apply? Only if you believe that plants have minds. In other words, it’d be a stretch! This highlights the uniqueness of the biopsychosocial model of psychology: The mind is central to understanding behavior and mental processes.

Behaviorists neglect the mind. Biological psychologists study the mind as the brain. By considering a person’s mental state in the context of the biological systems and social environment, biopsychosocial psychologists get a broader view of a person’s behavior and mental state than those who focus exclusively on one aspect of the three-part model.

Observing the role of the outside world

Brains don’t work and minds don’t think in a vacuum. Behavior and mental processes are embedded within a context that includes other people and things in the environment in which people live. Therefore, the social aspect of the biopsychosocial model also includes parent-child relationships, families, communities, and culture.

Other people have enormous power in shaping and influencing an individual’s behavior and mental processes. If you’re unsure, consider the detrimental effects that negative social events or experiences, such as physical or sexual abuse, can have on a person. Overlooking the impact of a person’s interaction with family and friends is to neglect reality.

Do behaviors and mental processes vary across cultures? Let me put the question to you this way: If I only conducted research with white, middle-class, college students, can I state that my results apply to all people? Definitely not. This subject has been a hot topic in psychology over the last 30 years or so. Technological advances help make our world a smaller place and different cultures come into contact with each other more often than ever before, making a person’s social life increasingly complex. Thus, just as the influence of family and friend relations is critical, it is also vital that psychologists consider cultural differences.

So it’s safe to say that the culture in which an individual is raised as well as the cultures he experiences or adopts throughout life impact his behavior and mental processes.

Cultural influence needs to be addressed in psychology for at least two reasons:

Image Science seeks objectivity and truth. Everyone is vulnerable to cultural bias, and psychologists are no exception. Therefore, psychology should try to identify the influence of culture on their own thinking, theories, and research in order to provide the most objective and complete picture of reality possible.

Image Accuracy depends on the relativity of truth in a specific culture. So, just because research with Americans shows that using baby talk to communicate with infants stunts the growth of mature speech, this doesn’t mean that these findings hold true in other countries.

Resolving the Nature versus Nurture Debate

Consider professional athletes, those elite performers who are lucky enough to get paid to play games for a living. How much luck do you think is really involved? A common misconception about professional, elite athletes is that their natural raw talent accounts for their success. Yet anyone who has worked with or known one of these individuals will tell you that hard work has a lot to do with his success.

So which is it? Talent or hard work? This question lies at the heart of a long-running debate within psychology; it’s known as the nature versus nurture debate. Talent versus hard work. Inborn ability versus learning and effort.

Image Nature refers to the concept that behavior and mental processes are innate, inborn, and hard-wired and will unfold over time as a person develops and her genetic blueprint is revealed. Nurture refers to the idea that behavior and mental processes are not inborn and instead are learned from the environment in which people live.

Both perspectives have their proponents. John Locke, a 17th-century British philosopher, espoused the concept of tabula rasa, the “blank slate” and believed that, given the right learning experiences, a person can become anything in life. On the other side is Charles Darwin, the father of evolution and nature advocate, who believed that a person’s destiny is found in his biology and genes.

A quote by John Watson, considered by some historians as the founder of behaviorism, epitomizes this perspective:

Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I’ll guarantee to take any one at random and train him to become any type of specialist I might select — doctor, lawyer, artist, merchant-chief, and, yes, even beggarman and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors. I am going beyond my facts and I admit it, but so have the advocates of the contrary and they have been doing it for many thousands of years.

— John B. Watson, Behaviorism, 1930

Most modern psychologists consider this debate over. The simple answer is that both nature and nurture impact a person’s behavior and level of success. This means that making sense of what people do and why they do it is ultimately accomplished only by investigating and understanding the relative contributions of innate biological influences and learned environmental influences.

Branching Off

Fundamentally, psychologists are scientists who are armed with metatheory, the biopsychosocial model, research, and data as they go about their business. There are three main types of psychologists:

Image Experimental psychologists spend the majority of their time conducting research and teaching, and they often work in academic settings. Experimental psychology covers a wide range of topics, but individual researchers typically have a specialty such as social psychology or developmental psychology.

Image Applied psychologists directly apply research findings and psychological theory to everyday settings and problems. Applied psychologists work in a wide variety of settings, such as business, government, education, and even sports. Popular areas of applied psychology include Industrial/Organizational Psychology, Forensic Psychology, and Military Psychology.

Image Clinical psychologists study, diagnose, and treat psychological problems.

Of course, some psychologists fit in more than one of these categories, for example, clinical psychologists conducting research.

The American Psychological Association states that in order for an individual to be considered a psychologist, he or she must possess a doctoral degree (a PhD, PsyD, or EdD, for example), and although requirements may vary from country to country, this is a generally accepted standard in much of the world as well. And nearly all US states require the individual to obtain a license to practice psychology, which typically involves taking an intensive licensing exam. In the United Kingdom, the British Psychological Society requires doctoral-level training in order to practice as a clinical psychologist, and practitioners are regulated by the Health and Care Professions Council.

Considering ethics

Human conduct is guided by codes of behavior known as ethics. Simply put, ethics refers to the prescribing of right behavior and the proscribing of wrong behavior. In addition to psychologists being guided by the principles of science, they are also guided by their own code of ethics, their own understanding of right and wrong behavior.

The American Psychological Association (APA; visit its website, is the largest organization in the world representing psychology as a profession. Other countries, including the UK, have their own professional bodies, with similar regulatory frameworks. The mission of the APA is to advance the field of psychology and to benefit society. The APA's Ethical Principles of Psychologists and Code of Conduct is the ethical rule book for psychologists. The main components of this rulebook are the "General Principles" and specific "Ethical Standards." The Ethical Standards are numerous and cover topics ranging from resolution of ethical dilemmas to competence, education and training, and therapy.

Although all the ethical standards are important, the one that is often considered tantamount is the ethical principle of confidentiality — that information of a research participant or therapy client information is kept private and there are limits on how and when it can be disclosed to a third party. The APA’s code is enforceable for members of the association, and a breach of the code can result in expulsion from the association. Most state licensing boards in the United States have adopted the APA’s code as their guide and standard as well and can enforce compliance through various forms of disciplinary action including revoking licenses.

Generally speaking, the code of ethics is shaped by several overarching principles that compel psychologists to act in the best interest of the people they are working with or for (for example, clients, patients, students, or research subjects) and to avoid any harm. They are expected to act responsibly and with best practices in mind, with honesty and integrity. Basic human rights and dignity should be respected and justice should be preserved and pursued.

Seeking Truth

It seems that I’ve always been looking for the truth. When I was in college, I frequented a little bookstore near campus that specialized in spiritual, philosophical, and popular-psychology books. At least once a week, I would peruse the shelves looking for something interesting. The books were arranged by topic: metaphysics, Eastern wisdom, Western wisdom, Buddhism, Taoism, Judaism, Islam, Christianity, new age, channeling, and so on. I read books from every section. I was searching for some kind of ultimate truth, some kind of answer.

One day, I realized that I had sampled works from every section in this bookstore, but I still wasn’t satisfied. Then, I had a strange thought: This bookstore is full of opinions! How was I supposed to find the answers or the truth when I was only getting opinions? Many of the books contained testimonials, logical arguments, and stories, but very little, if any, evidence or proof. If I questioned something, I simply had to take an author’s word for it and trust it was true. But they couldn’t all be right because some authors contradicted or criticized others. So who was right?

I guess I’m just one of those people who needs proof. It would be an exaggeration to say that I’m finding all the answers in psychology, but, as a field, psychology makes a serious effort to establish the truth of its claims with proof, or empirical evidence, which comes from applying the empirical method, an approach to truth that uses observation and experiment.

Psychology, as the scientific study of human behavior and mental processes, uses the empirical method. It relies on data and information obtained from research, experimentation, observation, and measurement. The empiricist motto is Show me the data. This is not to deny the importance of theory. But theory is insufficient as a working position for reliable psychologists.

Psychologists act responsibly when they are working with empirical evidence and less responsibly when not. These scientists are expected to base their work on solid data and information, not opinion.

From an empirical perspective, just because a psychologist says something doesn’t make it true. A psychologist is compelled to base her claims on empirical evidence gathered from research and statistical analysis. Is it really worth paying for a psychologist’s services to treat depression or a phobia, for example, if what she is saying and doing is just based on her opinion? What makes her the expert? You expect professionals to possess a credible amount of specific knowledge about their area of expertise, and this knowledge and expertise should be based on empirical evidence.

The authority of these experts is maintained through the ways in which they know and investigate their subject matter.

Words like knowledge and truth can be tricky sometimes. Knowing where psychologists’ knowledge comes from is an important first step in learning about psychology. In this section, I explore the different ways that psychologists gather evidence and try to substantiate the truth of their claims and knowledge. Specifically, I describe scientific research and theory development, the two primary tools psychologists use to establish expertise in human behavior and mental processes.

Applying the scientific method

Most everyone has an opinion about the behavior and mental processes of others and ourselves. “She left you because you’re emotionally unavailable.” “If you don’t express yourself, it just stays bottled up inside.” We’re full of answers to the why, how, and what questions regarding people. But how do we really know that not talking about feelings leads to bottling them up? I may think that not expressing feelings allows them to drift away like clouds on a windy day. Who’s right? You may be thinking that it doesn’t matter, but we’ve got this whole group of psychologists who claim to be experts on these matters. On what grounds can they make this claim to expertise?

Psychologists strive to maintain their expertise and knowledge through the use of three forms of knowledge acquisition or ways of knowing:

Image Authority: Utilized to transmit information, usually in a therapy setting or the education and training process. Patients and students don’t have time to go out and research everything that they’re told. They have to take someone’s word for it at some point.

Image Rationalism/logic: Used to create theories and hypotheses. If things don’t make logical sense, they probably won’t make sense when researchers use the scientific method to investigate them.

Image Scientific method: Used as the preferred method of obtaining information and investigating behavior and mental processes. Psychologists implement the scientific method through a variety of different techniques.

Image Let me be perfectly clear: Not everything that psychologists do, talk about, and believe is based on scientific research. A lot of stuff is based on the authority of well-known personalities in the field. Other knowledge is based on clinical experience without any systematic investigation. A good-sized chunk of information that’s out there is also purely theoretical, but it makes sense on rational or 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 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!

Image Scientists should never change their experimental data to match their original theory; that’s cheating!

Developing a good theory

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. Knowing this is important because a significant amount of psychological knowledge is based on theory. Theories perform two main functions: They combine what is already known into a simpler package of knowledge and they help psychologists plan future investigations: Theories summarize and guide.

Theories and hypotheses are similar but not exactly the same thing. Psychologists test theories by studying their logical implications. Hypotheses are specific predictions based on these implications. You can add new information to theories, and you can use existing theories to generate new ones.

Image Not every theory is a good theory. In order for a theory to be good, it must meet three criteria:

Image Parsimony: It must be the simplest explanation possible that still explains the available observation.

Image Precision: It must make precise, not overly large or vague, statements about reality.

Image Testability: It must lend itself to scientific investigation. There must be some way to show that the theory can be wrong. It is easy to collect more information consistent with one’s theory. It is braver to be a scientist: to examine situations that may prove one’s theory wrong.

Researching Matters

Psychologists use two broad categories of research when they want to scientifically evaluate a theory: descriptive research and experimental research. In this section, I describe these approaches and dig into matters related to statistics, understanding cause and effect in correlational studies, and the fascinating placebo effect.

Understanding descriptive research

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.

Doing experimental research

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 about 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 is, “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 after strangers at a bus stop have been there for five minutes, they will start having a conversation. How can I test my hypothesis?

I can just hang out at a bus stop and watch to see if it happens. But how do I know that my five-minute-or-more rule is behind my observations? I don’t. It maybe any number of things. This is a problematic issue in research I like to call the z-factor. A z-factor is something affecting the hypothesis that I am unaware of or not accounting for. It is an extraneous variable that I need to control in order to have confidence in my theory. Some possible z-factors in the bus-stop study may be culture, age, and time of day. Good research studies try to eliminate z-factors or extraneous variables by controlling for their influence and factoring them out of the explanation.

A descriptive or observational study won’t account for z-factors, so instead I set up an experiment in which I approach people at bus stops and try a variety of things to test my hypothesis. I may go up and try to talk to someone after two minutes. I may wait for ten minutes. I may conduct studies during a thunderstorm or while dressed in particular ways, and I would try to prove my hypothesis wrong! I seek to find that people have conversations at bus stops before five minutes. If this is the case, then the five-minute rule is inaccurate. The more often I fail to prove my five-minute-or-more rule wrong, the more it deserves my confidence.

This is confusing. Why would I try to disprove my hypothesis instead of just proving it right? In any scientific investigation, I can never really prove a hypothesis true. Instead, I set out to disprove the opposite of my hypothesis. For example, people once thought the earth was flat. Everything observed at that time was consistent with this idea. However, someone came along and provided evidence that disputed this idea, which showed the flaw in the thinking. If I have a hypothesis and I keep finding evidence for it, I can be more and more confident in my hypothesis but never really know for sure. But if I can find just one example that contradicts my hypothesis, then this casts doubt on my hypothesis. If I say all swans are white, what happens when I find one black swan? The notion that all swans are white is false!

Measuring one, measuring all with statistics

Good psychology is based on solid theory and good data, whether the data is obtained through observation or experimentation. And psychology claims to make statements about all people. That is, psychologists claim that their research applies to people in general most of the time. They seek the truth as it applies to all people. But without conducting research on everyone on Earth, how can psychologists possibly make this claim?

A branch of mathematics called statistics comes riding in on a white horse to enable a psychologist to make claims about humanity based on studies and research conducted on only a few dozen or a couple hundred people. After a theory is developed, the scientific method dictates that that theory then be put to the test, either through observation or experimentation. Again, we run into the problem of not being able to observe or experiment with everyone and this is where statistics helps out.

Statistics is concerned with the rules of data collection and analysis. Generally, two types of statistical analyses are used in psychology, descriptive and inferential:

Image Descriptive statistics refer to the direct numerical measurement of characteristics of a population such as how many of something there are, what the average number of some phenomenon is, or what the range of a particular value of something is. I am describing what is there, but not going beyond the data. If I conduct descriptive statistics on all swans to test my hypothesis that all swans are white, I would have to describe every swan. Formally, a population is defined as a well-defined, complete collection of things, objects, and so on. A descriptive analysis requires a description of the entire swan population.

Image Inferential statistics comes to the rescue when I can’t measure all swans, because this approach allows me to measure a sample of swans, a subset of the swan population, and then make inferences or estimates about the population as a whole from the sample that was drawn.

Inferential statistics solves the measurement dilemma as long, of course, as you follow some basic rules such as randomization and appropriate sample size.

Image Randomization allows researchers to make inferences about a population based on the way a sample is chosen. Every member of the population must have the same chance of being in the sample.

Collecting a random sample ensures that the population is well represented. If you don’t randomly choose the people to measure, then you can fall prey to sampling bias, choosing in a way so that some members of the population are less likely to be included than others. Sampling bias prevents you from being able to make statements about an entire population.

This issue often comes up in the use of polls during election season. A pollster claims that a result from measuring a sample extends to the population of likely voters, and critics are quick to point out that the sample consisted of 20- to 25-year-old graduate students at a liberal arts college in the Northwest. Is this a representative sample of likely voters?

Another key ingredient to ensuring that your sample is representative of the population is sample size, the number or n of individuals in your sample. Certainly the larger the sample the better because you get closer to measuring the population more directly and less inference is required. Of course, the size of your sample, your n, is determined by logistics and practicality so you typically have to settle for something much smaller than anything approaching the total population.

This brings up a pet peeve for psychologists, and scientists in general, known as the “N of One” problem. Everyone gets advice and information from friends about dieting and nutrition. My buddy tried the “caveman diet” and swears he lost 40 lbs. My officemate was on the “cupcake” diet and lost 20 lbs. My cousin was on the “carbs only” diet and gained 100 lbs. These people are offering data from their own experience. However, they have only sampled one individual from the population, themselves. They have a sample size of one. So, from a statistical perspective, how likely is it that their sample represents the population as a whole? Not likely at all. Correspondingly, this is why most people are more likely to trust advice if the same data comes from multiple people.

Relating variables: Correlation versus causation

A variable is the thing, characteristic, behavior, or mental process that is being measured or observed. Psychologists are interested in how variables relate, that is how do the things that are measured affect, impact, or alter each other? How does child abuse affect school performance? How does work stress affect depression? How does obsessive thinking affect relationships? In research, there are two types of variables, independent and dependent. A dependent variable is the thing that is impacted or altered as a function of the independent variable. The independent variable impacts the dependent variable as it changes.

My pulse and heart rate go way up when I am involved in a near-miss car accident situation. The dependent variable is my heart rate. The independent variable is the near miss. So, the near miss causes my heart rate to go up. This is a causal relationship. The value of the dependent variable is directly caused or influenced by the independent variable.

Does that mean that if two variables are related that there is a causal relationship? No, sometimes variables can be involved in a non-causal manner known as a correlation or a correlational relationship. A correlation exists between two variables when the value of one is related to the value of the other but not necessarily in a causal manner. For example, a semifamous correlation is that the crime rate tends to be higher in the summer months. So, there is a relationship between heat and crime rate; when one is high, the other is too. But does that mean that hot weather causes crime to go up? Not necessarily, it can be rather that youth and adolescents have more free time on their hands and therefore get into more trouble and commit more crime. This is conjecture of course and is just to prove the point that simply because hot weather and crime are related does not mean that one causes the other to happen. Correlation, not causation.

Doing nothing is something: The placebo effect

Psychologists want to test the impact of independent variables on dependent variables. They may want to test the impact of a new medication (independent variable) on levels of anxiety (dependent variable). This can be done by comparing people with anxiety who get the medication with those who do not. If anxiety goes down (or up), then maybe the medication is helping (or making things worse). This is considered a simple experimental and control group approach. An experimental group is the group that is getting the independent variable, and the control group is not; it is getting nothing in essence.

This is a solid experimental approach but there is another variation of this approach that is often used to help make the impact of the independent variable stand out more. This is done by using a placebo group in addition to the control group. A placebo is a decoy variable of sorts, a fake independent variable that is not expected to have an impact on the dependent variable, but the person in the study thinks it is an actual treatment or independent variable. Of course, some psychologists fit in more than one of these categories, for example, clinical psychologists conducting research.

From the preceding anxiety example, there would then be three groups, the medication group (independent variable group), the no-medication group (control group), and the placebo medication group (another control group). So, if at the end of the experiment the findings are that the medication group’s anxiety went down substantially, we can conclude the medication worked right? This can be said only in contrast to the no-medication group. But with the placebo group, another level of confidence exists because sometimes in studies like this both the independent variable and the placebo group show change. That would shed doubt on the trustworthiness of the finding from the independent variable group. But if the independent variable group shows change and neither the control group nor the placebo group showed change, we can be that much more confident in that finding.

What is interesting about this, however, is that the placebo group quite often shows change or improvement. This is known as the placebo effect, when an experimental effect is related to the presence of the placebo. For example, it is amazing how often a sugar pill (placebo) produces reductions in anxiety in experimental subjects. This truly fascinating phenomenon is one that scientists from all fields are trying to learn more about but have not quite figured out yet.

The rest of this book introduces you to various theories and research. There’s a lot of stuff in here! Because psychology is about people, some people may argue that everything about people is psychology. I couldn’t write a book about everything. This is not Everything About People For Dummies. In establishing a way to decide what to put in the book and what not to, I used scientific research and theory as my measuring rod. The information you find in this book is considered part of legitimate psychological science and theory.