10 Developing a Hypothesis
Learning Objectives
- Distinguish between a theory and a hypothesis.
- Discover how theories are used to generate hypotheses and how the results of studies can be used to further inform theories.
- Understand the characteristics of a good hypothesis.
Theories and Hypotheses
Before describing how to develop a hypothesis, it is important to distinguish between a theory and a hypothesis. A theory is a coherent explanation or interpretation of one or more phenomena. Although theories can take a variety of forms, one thing they have in common is that they go beyond the phenomena they explain by including variables, structures, processes, functions, or organizing principles that have not been observed directly. Consider, for example, Zajonc’s theory of social facilitation and social inhibition (1965)[1]. He proposed that being watched by others while performing a task creates a general state of physiological arousal, which increases the likelihood of the dominant (most likely) response. So for highly practiced tasks, being watched increases the tendency to make correct responses, but for relatively unpracticed tasks, being watched increases the tendency to make incorrect responses. Notice that this theory—which has come to be called drive theory—provides an explanation of both social facilitation and social inhibition that goes beyond the phenomena themselves by including concepts such as “arousal” and “dominant response,” along with processes such as the effect of arousal on the dominant response.
Outside of science, referring to an idea as a theory often implies that it is untested—perhaps no more than a wild guess. In science, however, the term theory has no such implication. A theory is simply an explanation or interpretation of a set of phenomena. It can be untested, but it can also be extensively tested, well supported, and accepted as an accurate description of the world by the scientific community. The theory of evolution by natural selection, for example, is a theory because it is an explanation of the diversity of life on earth—not because it is untested or unsupported by scientific research. On the contrary, the evidence for this theory is overwhelmingly positive and nearly all scientists accept its basic assumptions as accurate. Similarly, the “germ theory” of disease is a theory because it is an explanation of the origin of various diseases, not because there is any doubt that many diseases are caused by microorganisms that infect the body.
A hypothesis, on the other hand, is a specific prediction about a new phenomenon that should be observed if a particular theory is accurate. It is an explanation that relies on just a few key concepts. Hypotheses are often specific predictions about what will happen in a particular study. They are developed by considering existing evidence and using reasoning to infer what will happen in the specific context of interest. Hypotheses are often but not always derived from theories. So a hypothesis is often a prediction based on a theory but some hypotheses are a-theoretical and only after a set of observations have been made, is a theory developed. This is because theories are broad in nature and they explain larger bodies of data. So if our research question is really original then we may need to collect some data and make some observations before we can develop a broader theory.
Theories and hypotheses always have this if-then relationship. “If drive theory is correct, then cockroaches should run through a straight runway faster, and a branching runway more slowly, when other cockroaches are present.” Although hypotheses are usually expressed as statements, they can always be rephrased as questions. “Do cockroaches run through a straight runway faster when other cockroaches are present?” Thus deriving hypotheses from theories is an excellent way of generating interesting research questions.
But how do researchers derive hypotheses from theories? One way is to generate a research question using the techniques discussed in this chapter and then ask whether any theory implies an answer to that question. For example, you might wonder whether expressive writing about positive experiences improves health as much as expressive writing about traumatic experiences. Although this question is an interesting one on its own, you might then ask whether the habituation theory—the idea that expressive writing causes people to habituate to negative thoughts and feelings—implies an answer. In this case, it seems clear that if the habituation theory is correct, then expressive writing about positive experiences should not be effective because it would not cause people to habituate to negative thoughts and feelings. A second way to derive hypotheses from theories is to focus on some component of the theory that has not yet been directly observed. For example, a researcher could focus on the process of habituation—perhaps hypothesizing that people should show fewer signs of emotional distress with each new writing session.
Among the very best hypotheses are those that distinguish between competing theories. For example, Norbert Schwarz and his colleagues considered two theories of how people make judgments about themselves, such as how assertive they are (Schwarz et al., 1991)[2]. Both theories held that such judgments are based on relevant examples that people bring to mind. However, one theory was that people base their judgments on the number of examples they bring to mind and the other was that people base their judgments on how easily they bring those examples to mind. To test these theories, the researchers asked people to recall either six times when they were assertive (which is easy for most people) or 12 times (which is difficult for most people). Then they asked them to judge their own assertiveness. Note that the number-of-examples theory implies that people who recalled 12 examples should judge themselves to be more assertive because they recalled more examples, but the ease-of-examples theory implies that participants who recalled six examples should judge themselves as more assertive because recalling the examples was easier. Thus the two theories made opposite predictions so that only one of the predictions could be confirmed. The surprising result was that participants who recalled fewer examples judged themselves to be more assertive—providing particularly convincing evidence in favor of the ease-of-retrieval theory over the number-of-examples theory.
Theory Testing
The primary way that scientific researchers use theories is sometimes called the hypothetico-deductive method (although this term is much more likely to be used by philosophers of science than by scientists themselves). Researchers begin with a set of phenomena and either construct a theory to explain or interpret them or choose an existing theory to work with. They then make a prediction about some new phenomenon that should be observed if the theory is correct. Again, this prediction is called a hypothesis. The researchers then conduct an empirical study to test the hypothesis. Finally, they reevaluate the theory in light of the new results and revise it if necessary. This process is usually conceptualized as a cycle because the researchers can then derive a new hypothesis from the revised theory, conduct a new empirical study to test the hypothesis, and so on. As Figure 2.2 shows, this approach meshes nicely with the model of scientific research in psychology presented earlier in the textbook—creating a more detailed model of “theoretically motivated” or “theory-driven” research.
As an example, let us consider Zajonc’s research on social facilitation and inhibition. He started with a somewhat contradictory pattern of results from the research literature. He then constructed his drive theory, according to which being watched by others while performing a task causes physiological arousal, which increases an organism’s tendency to make the dominant response. This theory predicts social facilitation for well-learned tasks and social inhibition for poorly learned tasks. He now had a theory that organized previous results in a meaningful way—but he still needed to test it. He hypothesized that if his theory was correct, he should observe that the presence of others improves performance in a simple laboratory task but inhibits performance in a difficult version of the very same laboratory task. To test this hypothesis, one of the studies he conducted used cockroaches as subjects (Zajonc, Heingartner, & Herman, 1969)[3]. The cockroaches ran either down a straight runway (an easy task for a cockroach) or through a cross-shaped maze (a difficult task for a cockroach) to escape into a dark chamber when a light was shined on them. They did this either while alone or in the presence of other cockroaches in clear plastic “audience boxes.” Zajonc found that cockroaches in the straight runway reached their goal more quickly in the presence of other cockroaches, but cockroaches in the cross-shaped maze reached their goal more slowly when they were in the presence of other cockroaches. Thus he confirmed his hypothesis and provided support for his drive theory. (Zajonc also showed that drive theory existed in humans [Zajonc & Sales, 1966][4] in many other studies afterward).
Incorporating Theory into Your Research
When you write your research report or plan your presentation, be aware that there are two basic ways that researchers usually include theory. The first is to raise a research question, answer that question by conducting a new study, and then offer one or more theories (usually more) to explain or interpret the results. This format works well for applied research questions and for research questions that existing theories do not address. The second way is to describe one or more existing theories, derive a hypothesis from one of those theories, test the hypothesis in a new study, and finally reevaluate the theory. This format works well when there is an existing theory that addresses the research question—especially if the resulting hypothesis is surprising or conflicts with a hypothesis derived from a different theory.
To use theories in your research will not only give you guidance in coming up with experiment ideas and possible projects, but it lends legitimacy to your work. Psychologists have been interested in a variety of human behaviors and have developed many theories along the way. Using established theories will help you break new ground as a researcher, not limit you from developing your own ideas.
Characteristics of a Good Hypothesis
There are three general characteristics of a good hypothesis. First, a good hypothesis must be testable and falsifiable. We must be able to test the hypothesis using the methods of science and if you’ll recall Popper’s falsifiability criterion, it must be possible to gather evidence that will disconfirm the hypothesis if it is indeed false. Second, a good hypothesis must be logical. As described above, hypotheses are more than just a random guess. Hypotheses should be informed by previous theories or observations and logical reasoning. Typically, we begin with a broad and general theory and use deductive reasoning to generate a more specific hypothesis to test based on that theory. Occasionally, however, when there is no theory to inform our hypothesis, we use inductive reasoning which involves using specific observations or research findings to form a more general hypothesis. Finally, the hypothesis should be positive. That is, the hypothesis should make a positive statement about the existence of a relationship or effect, rather than a statement that a relationship or effect does not exist. As scientists, we don’t set out to show that relationships do not exist or that effects do not occur so our hypotheses should not be worded in a way to suggest that an effect or relationship does not exist. The nature of science is to assume that something does not exist and then seek to find evidence to prove this wrong, to show that it really does exist. That may seem backward to you but that is the nature of the scientific method. The underlying reason for this is beyond the scope of this chapter but it has to do with statistical theory.
- Zajonc, R. B. (1965). Social facilitation. Science, 149, 269–274 ↵
- Schwarz, N., Bless, H., Strack, F., Klumpp, G., Rittenauer-Schatka, H., & Simons, A. (1991). Ease of retrieval as information: Another look at the availability heuristic. Journal of Personality and Social Psychology, 61, 195–202. ↵
- Zajonc, R. B., Heingartner, A., & Herman, E. M. (1969). Social enhancement and impairment of performance in the cockroach. Journal of Personality and Social Psychology, 13, 83–92. ↵
- Zajonc, R.B. & Sales, S.M. (1966). Social facilitation of dominant and subordinate responses. Journal of Experimental Social Psychology, 2, 160-168. ↵
Learning Objectives
- Define human subjects research
- Describe and provide examples of nonhuman subjects that researchers might examine
- Define institutional review boards and describe their purpose
- Distinguish between the different levels of review conducted by institutional review boards
In 1998, actor Jim Carey starred in the movie The Truman Show. [1] At first glance, the film appears to depict a perfect research experiment. Just imagine the possibilities if we could control every aspect of a person’s life, from where that person lives, to where they work, their lifestyle, and whom they marry. Of course, keeping someone in a bubble of your creation and sitting back to watch how they fare would be highly unethical, not to mention illegal. However, the movie clearly inspires thoughts about the differences between scientific research and research on nonhumans. One of the most exciting, albeit challenging, aspects of conducting social work research is that most of our studies involve human subjects. The free will and human rights of the people we study will always have an impact on what we are able to research and how we are able to conduct that research.
Human research versus nonhuman research
While all research comes with its own set of ethical concerns, those associated with research conducted on human subjects vary dramatically from those of research conducted on nonliving entities. The US Department of Health and Human Services (USDHHS) defines a human subject as “a living individual about whom an investigator (whether professional or student) conducting research obtains (1) data through intervention or interaction with the individual, or (2) identifiable private information” (USDHHS, 1993, para. 1). [2] Some researchers prefer to use the term “participants” as opposed to “subjects,” as it acknowledges the agency of the people who participate in the study. For our purposes, we will use the two terms interchangeably.
In some states, human subjects also include deceased individuals and human fetal materials. On the other hand, nonhuman research subjects are objects or entities that investigators manipulate or analyze in the process of conducting unobtrusive research projects. Nonhuman research subjects can include sources such as newspapers, historical documents, clinical notes, television shows, buildings, and even garbage. Unsurprisingly, research on human subjects is regulated much more heavily than research on nonhuman subjects. However, there are ethical considerations that all researchers must consider regardless of their research subject. We’ll discuss those considerations in addition to concerns that are unique to research on human subjects.
A historical look at research on humans
Research on humans hasn’t always been regulated in the way that it is today. The earliest documented cases of research using human subjects are of medical vaccination trials (Rothman, 1987). [3] One such case took place in the late 1700s, when scientist Edward Jenner exposed an 8-year-old boy to smallpox in order to identify a vaccine for the devastating disease. Medical research on human subjects continued without much law or policy intervention until the end of World War II, when Nazi doctors and scientists were put on trial for conducting human experimentation, during the course of which they tortured and murdered many concentration camp inmates (Faden & Beauchamp, 1986). [4] The trials conducted in Nuremberg, Germany resulted in the creation of the Nuremberg Code, a 10-point set of research principles designed to guide doctors and scientists who conduct research on human subjects. Today, the Nuremberg Code guides medical and other research conducted on human subjects, including social scientific research.
Medical scientists are not the only researchers who have conducted questionable research on humans. In the 1960s, psychologist Stanley Milgram (1974) [5] conducted a series of experiments designed to understand obedience to authority in which he tricked subjects into believing they were administering an electric shock to other subjects. The electric shocks were not real at all, however some of Milgram’s research participants experienced extreme emotional distress after the experiment (Ogden, 2008). [6] A reaction of emotional distress is understandable. The realization that you are willing to administer painful shocks to another human being, just because someone who looked authoritative told you to do so, might indeed be traumatizing. This can be true even after you learn that the chocks you administered were not real.
Around the same time that Milgram conducted his experiments, sociology graduate student Laud Humphreys (1970) [7] was collecting data for his dissertation research on the tearoom trade, which was the practice of men engaging in anonymous sexual encounters in public restrooms. Humphreys wished to understand who these men were and why they participated in the trade. To conduct his research, Humphreys offered to serve as a “watch queen,” the person who watches for police and gets to watch the sexual encounters, in a local park restroom where the tearoom trade was known to occur. What Humphreys did not do was identify himself as a researcher to his subjects. Instead, he watched them for several months, getting to know them while learning more about the tearoom trade practice. And, without the knowledge of his research subjects, he would jot down their license plate numbers as they entered and exited the parking lot near the restroom.
After participating as a watch queen, Humphreys utilized the license plate numbers and his insider connections with the local motor vehicle registry to obtain the names and home addresses of his research subjects. Then, disguised as a public health researcher, Humphreys visited his subjects in their homes and interviewed them about their lives and their health. Humphreys’ research dispelled a good number of myths and stereotypes about the tearoom trade and its participants. He learned, for example, that over half of his subjects were married to women and many of them did not identify as gay or bisexual. [8]
When Humphreys’ work became public, he was met with much controversy from his home university, fellow scientists, and the entire public, as his study raised many concerns about the purpose and conduct of social science research. His work was so ethically problematic that the chancellor of his university even tried to have his degree revoked. In addition, the Washington Post journalist Nicholas von Hoffman wrote the following warning about “sociological snoopers”:
We’re so preoccupied with defending our privacy against insurance investigators, dope sleuths, counterespionage men, divorce detectives and credit checkers, that we overlook the social scientists behind the hunting blinds who’re also peeping into what we thought were our most private and secret lives. But they are there, studying us, taking notes, getting to know us, as indifferent as everybody else to the feeling that to be a complete human involves having an aspect of ourselves that’s unknown (von Hoffman, 1970). [9]
In the original version of his report, Humphreys defended the ethics of his actions. In 2008, years after Humphreys’ death, his book was reprinted with the addition of a retrospect on the ethical implications of his work. [10] In his written reflections on his research and its resulting fallout, Humphreys maintained that his tearoom observations constituted ethical research on the grounds that those interactions occurred in public places. But Humphreys added that he would conduct the second part of his research differently. Rather than trace license numbers and interview unwitting tearoom participants in their homes under the guise of public health research, Humphreys instead would spend more time in the field and work to cultivate a pool of informants. Those informants would know that he was a researcher and would be able to fully consent to being interviewed. In the end, Humphreys concluded “there is no reason to believe that any research subjects have suffered because of my efforts, or that the resultant demystification of impersonal sex has harmed society” (Humphreys, 2008, p. 231). [10]
With the increased regulation of social scientific research, it is unlikely that researchers would be permitted to conduct projects like Humphreys' in today's world. Some argue that Humphreys’ research was deceptive, put his subjects at risk of losing their families and their positions in society, and was therefore unethical (Warwick, 1973; Warwick, 1982). [11] Others suggest that Humphreys’ research “did not violate any premise of either beneficence or the sociological interest in social justice” and that the benefits of Humphreys’ research, namely the dissolution of myths about the tearoom trade specifically and human sexual practice more generally, outweigh the potential risks associated with the work (Lenza, 2004, p. 23). [12] What do you think, and why?
These and other studies (Reverby, 2009) [13] led to increasing public awareness and concern regarding research on human subjects. In 1974, the US Congress enacted the National Research Act, which created the National Commission for the Protection of Human Subjects in Biomedical and Behavioral Research. The commission produced The Belmont Report, a document outlining basic ethical principles for research on human subjects (National Commission for the Protection of Human Subjects in Biomedical and Behavioral Research, 1979). [14] The National Research Act (1974) [15] also required that all institutions receiving federal support establish institutional review boards (IRBs) to protect the rights of human research subjects. Since that time, many private research organizations that do not receive federal support have also established their own review boards to evaluate the ethics of the research that they conduct.
Institutional Review Boards (IRBs)
Institutional Review Boards, or IRBs, are tasked with ensuring that the rights and welfare of human research subjects will be protected at all institutions, including universities, hospitals, nonprofit research institutions, and other organizations that receive federal support for research. IRBs typically consist of members from a variety of disciplines, such as sociology, economics, education, social work, and communications. Most IRBs also include representatives from the community in which they reside. For example, representatives from nearby prisons, hospitals, or treatment centers might sit on the IRBs of university campuses near them. The diversity of membership ensures that the complex ethical issues of human subjects research will be considered fully by a knowledgeable, experienced panel. Investigators conducting research on human subjects are required to submit proposals outlining their research plans to IRBs for review and approval prior to beginning their research. Even students who conduct research on human subjects must have their proposed work reviewed and approved by the IRB before beginning any research (though, on some campuses, some exceptions are made for classroom projects that will not be shared outside of the classroom).
The IRB has three levels of review, defined in statute by the USDHHS. Exempt review is the lowest level of review. Exempt studies expose participants to the least potential for harm and often involve little participation by the human subjects. In social work, exempt studies often examine data that is publicly available or secondary data from another researcher that has been de-identified by the person who collected it. Expedited review is the middle level of review. Studies considered under expedited review do not have to go before the full IRB board because they expose participants to minimal risk. However, the studies must be thoroughly reviewed by a member of the IRB committee. While there are many types of studies that qualify for expedited review, the most relevant to social workers include the use of existing medical records, recordings (such as interviews) gathered for research purposes, and research on individual group characteristics or behavior. Finally, the highest level of review is called a full board review. When researchers submit a proposal under full board review, the full IRB board will meet, discuss any questions or concerns with the study, invite the researcher to answer questions and defend their proposal, and vote to approve the study or send it back for revision. Full board proposals pose greater than minimal risk to participants. They may also involve the participation of vulnerable populations, or people who need additional protection from the IRB. Vulnerable populations include pregnant women, prisoners, children, people with cognitive impairments, people with physical disabilities, employees, and students. While some of these populations can fall under expedited review in some cases, they will often require the full IRB's approval to study.
It may surprise you to hear that IRBs are not always popular or appreciated by researchers. Sometimes, researchers are concerned that the IRBs are well-versed in biomedical and experimental research and less familiar with the qualitative, open-ended nature of social work research. The members of IRBs often want specific details about your study. They may require you to describe aspects of your study, including but not limited to: the specific population you will be studying, observation methods, potential interview questions for participants, and any predictions you have about your findings. For example, it would be extraordinarily frustrating or nearly impossible to provide this level of detail for a large-scale group participant observation study.
Oftentimes, social science researchers cannot study controversial topics or use certain data collection techniques due to ethical concerns of the IRB. When important social research is not permitted by review boards, researchers may become frustrated (and rightfully so). The solution is not to do away with review boards, which serve a necessary and important function. Instead, an effort should be made to educate IRB members about the importance of social science research methods and topics.
Key Takeaways
- When it comes to conducting ethical research, the use of human subjects presents a unique set of challenges and opportunities.
- Research on human subjects has not always been regulated to the extent that it is today.
- All institutions receiving federal support for research must have an IRB. Research organizations that do not receive federal support often include IRBs as a part of their organizational structure, although they are not required.
- Researchers submit studies for IRB review at one of three levels, depending on the potential level of harm that the study may inflict on its subjects.
Glossary
Exempt review- lowest level of IRB review, used for studies with minimal risk of harm or low levels of human subject involvement
Expedited review- middle level of IRB review, used for studies with minimal risk of harm but greater levels of human subject involvement
Full board review- highest level of IRB review, used for studies with greater than minimal risk of harm to participants
Vulnerable populations- groups of people that may pose an additional risk for harm when studied; may be granted additional protections during an IRB review.