Hypothesis

A hypothesis states a proposed explanation of a phenomenon. A good hypothesis is brief, clear, concise, and provable. It is one of the cornerstones of the scientific method and its defining characteristic is its provisional nature. A hypothesis is not a statement of truth; it is a statement of a possible truth that is either proved or discarded after having been tested extensively. If proved, it becomes part of the theoretical structure of its field. Whether or not it proves true, the process of testing the hypothesis affects the subsequent generation of hypotheses in the field. In the natural sciences (such as biology, chemistry, physics, geology), the preferred method of proving a hypothesis is through experiment. While experiments are used in the social sciences, other ways to provide evidence to prove a hypothesis are also used. Hypotheses are essential components in guiding research, answering questions, and developing solutions.

Background

The scientific method is used in the natural sciences as a way to ask and answer scientific questions and to solve problems. The technique typically has six parts: propose a question, research the topic of the question, develop a hypothesis that may answer the questions and is based on the research, experiment and test the hypothesis, analyze the results and the data gathered during the experiment, and finally, decide whether the hypothesis was correct.

The hypothesis is grounded in existing knowledge, and many refer to it as an "educated guess." To that end, most hypotheses are embedded with implicit assumptions, and sometimes the knowledge against or within them has not been tested and proved.

The scientific method accounts for alternate explanations of a phenomenon by incorporating a control into the research. A control can be a statistical variable or a parallel situation in an experiment. For instance, in medicine, to test a new drug, a control group receives a placebo (ineffectual) treatment in order to compare the results of that group against the group receiving the new drug.

In the social sciences, hypotheses can be tested by referring to existing data or by collecting new data and analyzing statistics. It is crucial that the data be relevant to the hypothesis and that the method be appropriate to test the central hypothesis and its auxiliaries hypotheses.

Logical positivism, an early-twentieth-century philosophical approach to the acquisition of knowledge, argued that knowledge consists in what can be verified through logic or experimentation. Logical positivists argued that ideas have no meaning or value unless they can be empirically verified, and scientific knowledge is based in fact rather than in overarching theory or philosophy.

Karl Popper (1902–94) changed the emphasis on verification—the proving true of a proposition or hypothesis—to instead focus on falsification. That is, rather than proving a hypothesis true, scientists should work to prove it false. If a hypothesis cannot be proven false, it should not count as science. The negative emphasis, then, counteracts any bias a researcher may have while attempting to prove a hypothesis: falsification strives to purge bias from scientific method to produce objective results. Popper was also open to hypotheses arrived at unconventionally, such as those revealed in dreams. As long as the hypothesis can be tested and falsified, it does not matter where it originates.

The biggest challenges to Popper’s view were written by French physicist and mathematician Pierre Duhem (1861–1916), who argued that the refutation of hypotheses is often imprecise. If a theory has been refuted because a central hypothesis has failed to be verified, the theory might contain untested assumptions, referred to as "auxiliary hypotheses," that may have skewed the results, and it would be unknown whether the central hypothesis or one or more of the auxiliary hypotheses affected the result.

Some philosophers of science have suggested that falsifiability itself be measured and have developed formulae to assess the degree of corroboration of hypotheses and their auxiliaries and to pinpoint whether a particular falsification refers to a hypothesis or one of its auxiliaries.

Overview

Hypotheses come in several standard forms and state the relationship between variables. A simple hypothesis predicts a relationship between an independent variable and a dependent variable. (The dependent variable is the phenomenon the hypothesis attempts to explain. In experimental research, the dependent variable is the effect, and the independent variable is the presumed cause.) Complex hypotheses assert a relationship between multiple independent variables and a dependent variable or between an independent variable and multiple dependent variables.

A directional hypothesis is usually based on existing theory and predicts a relationship and the nature of the relationship. A nondirectional hypothesis can be written as a conditional statement such as "If a person watches progressively more television each week, he or she will gain weight" or "People who watch more television will be more likely to gain weight than people who watch less television."

Hypotheses can also be written as mathematical statements, such as Y = (f)X. They can also take the form of a continuous statement suggesting that the increase (or decrease) of one variable will be associated with the increase of the other variable(s), such as "Increased television viewing will correlate with higher body mass indexes."

Learning to create and test an appropriate hypothesis is vital in the scientific method, which is among the most important processes of producing new knowledge.

Bibliography

Anderson, David R., Kenneth P. Burnham, and William L. Thompson. "Null Hypothesis Testing: Problems, Prevalence, and an Alternative." Journal of Wildlife Management 64.4 (2000): 912–23. Print.

Buddenbaum, Judith M., and Katherine B. Novak. Applied Communication Research. Ames: Iowa UP, 2001. Print.

Dusek, Val. Philosophy of Technology. Oxford: Blackwell, 2006. Print.

Gimbel, Steven, ed. Exploring the Scientific Method. Chicago: U of Chicago P, 2011. Print.

Hoijtink, Herbert. Informative Hypotheses: Theory and Practice for Behavioral and Social Scientists. Boca Raton: Taylor, 2012. Print.

Kronfeldner, Maria E. "Darwinian ‘Blind’ Hypothesis Formation Revisited." Synthese 175.2 (2010): 193–218. Print.

Osherson, Daniel N., and Scott Weinstein. "On Advancing Simple Hypotheses." Philosophy of Science 57.2 (1990): 266–7. Print.

Rosenberg, Alex. Philosophy of Science. 3rd ed. New York: Routledge, 2012. Print.

Rowbottom, Darrell P. "Corroboration and Auxiliary Hypotheses: Duhem’s Thesis Revisited." Synthese 177.1 (2010): 139–49. Print.

Silver, Harvey F., R. Thomas Dewing, and Matthew J. Perini. Inference: Teaching Students to Develop Hypotheses, Evaluate Evidence, and Draw Logical Conclusions. Alexandria: Silver Strong & Associates, 2012. Print.