MID EXP - Formulating the Hypothesis

I. FORMULATING THE HYPOTHESIS

A. Learning Objectives:

◦ Learn the differences between experimental and nonexperimental hypotheses.
◦ Understand the components of a good experimental hypothesis.
◦ Explore where hypotheses come from.
◦ Learn how to conduct a literature search.

Understanding the learning objectives helps guide the research process. For example, knowing the difference between hypothesis types can influence study design and data interpretation.

II. HYPOTHESIS

A. Definition of Research Hypothesis:

◦ A specific, clear, and testable proposition or predictive statement about the possible outcome of a scientific research study.
◦ Based on a particular property of a population.
◦ Presumed differences between groups on a particular variable or relationships between variables.

A research hypothesis provides a foundation for scientific inquiry. For instance, predicting that "increased study time leads to higher test scores" sets the stage for empirical testing.

B. Nonexperimental Hypothesis:

◦ It is a statement of your predictions of how events, traits, or behaviors might be related—not a statement about cause and effect.
◦ Type of Design:
     ◦ Correlational
     ◦ Ex post facto
     ◦ Non-equivalent groups
     ◦ Longitudinal
     ◦ Cross-sectional
◦ Hypothesis Examples:
     ◦ The amount of TV viewing will be directly related to vocabulary size.
     ◦ Repressors will report fewer treatment-related side effects than will nonrepressors.
     ◦ Incandescent lighting (in Company A) will produce better performance than fluorescent lighting (in Company B).
     ◦ Firstborn children will show imitative behaviors after the birth of a sibling.
     ◦ Firstborns with a 4-month-old sibling will show more imitative behavior than firstborns with a 1-month-old sibling.

Nonexperimental hypotheses help identify relationships without implying causation. For example, stating that "increased social media use correlates with lower academic performance" does not imply one causes the other.

C. Experimental Hypothesis:

◦ A statement that is a tentative explanation of an event or behavior; it predicts the effects of specified antecedent conditions on a measured behavior.
◦ A premise that describes what a researcher in a scientific study hopes to demonstrate if certain conditions are met.

Experimental hypotheses allow for testing causal relationships. For instance, hypothesizing that "students who study in groups will score higher on tests" sets up an experiment to test this prediction.

III. The Characteristics of an Experimental Hypothesis

A. Basic Criteria:

◦ To be scientific, each hypothesis should meet certain basic criteria.
◦ Believing that something is true or interesting is not enough to make it a useful hypothesis.
◦ Hypotheses must be synthetic statements that are testable, falsifiable, parsimonious, and (we hope) fruitful.

Meeting these criteria ensures that hypotheses are robust and scientifically valid. For example, a testable hypothesis can be empirically evaluated through experimentation.

B. Synthetic Statement:

◦ A statement that can be either true or false.
◦ Nonsynthetic statements should be avoided at all costs.
◦ These fall into two categories: analytic or contradictory.
     ◦ Analytic - the statement is always true.
     ◦ Contradictory - the statement is always false.
◦ Use the “If-then” format to ensure that the statement is synthetic.

Using the "If-then" format helps clarify the relationship between variables. For example, "If students study more, then their test scores will improve" is a clear synthetic statement.

C. Testable Statement:

◦ A statement that can be tested because the means exist for manipulating antecedent conditions and for measuring the resulting behavior.

Testable statements enable researchers to design experiments that can confirm or refute the hypothesis. For instance, measuring test scores before and after implementing a new study method provides clear data.

D. Falsifiable Statements:

◦ A statement that is worded so that it is falsifiable, or disprovable, by experimental results.

Falsifiability is crucial for scientific inquiry. For example, stating "students who study at night will perform worse on tests" can be tested and potentially disproven.

E. Parsimonious Statements:

◦ A simple statement that is simple and does not require many supporting assumptions.
◦ A hypothesis allows us to focus our attention on the main factors that influence our dependent variable.

Parsimonious statements streamline research focus. For instance, "Increased exercise leads to weight loss" is straightforward and avoids unnecessary complexity.

F. Fruitful Statements:

◦ A statement that can lead to new studies.

Fruitful hypotheses inspire further research. For example, finding a correlation between sleep and academic performance may lead to studies exploring optimal sleep patterns for students.

G. Null Hypothesis:

◦ It states that, in the general population, there is no change, no difference, or no relationship.
◦ In the context of an experiment, Ho predicts that the independent variable (treatment) has no effect on the dependent variable (scores) for the population.

The null hypothesis serves as a baseline for comparison. For instance, if testing a new teaching method, the null hypothesis would state that there is no difference in student performance compared to traditional methods.

H. Alternative Hypothesis:

◦ It states that, in the general population there is a change, a difference, or a relationship.
◦ In the context of an experiment, Hi predicts that the independent variable (treatment) does have an effect on the dependent variable (scores) for the population.

The alternative hypothesis posits a potential outcome that researchers seek to support. For example, the alternative hypothesis might state that "students taught with the new method will perform better."

I. Nondirectional Hypothesis:

◦ A hypothesis that one experimental group will differ from another without specification of the expected direction of the difference.

Nondirectional hypotheses indicate a difference without predicting the nature of that difference. For example, stating "there will be a difference in test scores between groups" does not specify which group will perform better.

J. Directional Hypothesis:

◦ A scientific prediction stating (a) that an effect will occur and (b) whether that effect will specifically increase, or specifically decrease, depending on changes to the independent variable.
◦ Key words that distinguish a directional hypothesis are: higher, lower, more, less, increase, decrease, positive, and negative.

Directional hypotheses provide specific predictions about the nature of the effect. For example, "students who study in groups will score higher than those who study alone" clearly states the expected outcome.

IV. Where Hypotheses Come From

A. Inductive Model:

◦ Is the process of reasoning from specific cases to more general principles.
◦ Researchers use inductive reasoning to construct theories by creating explanations that account for empirical data (observations).

The inductive model helps researchers develop broader theories based on specific observations. For example, observing that students who study together often do better may lead to a theory about collaborative learning benefits.

B. Deductive Model:

◦ Is the process of reasoning from general principles to make predictions about specific instances.
◦ The deductive model is most useful for testing the principles of a theory.

The deductive model allows researchers to test hypotheses derived from established theories. For example, predicting that a specific teaching method will improve test scores based on prior research supports the deductive approach.

C. BUILDING ON PRIOR RESEARCH:

◦ Nonexperimental studies can suggest cause-and-effect explanations that can be translated into experimental hypotheses.
◦ Prior experimental research is an excellent source of hypotheses.

Building on existing research helps refine hypotheses and ensures they are grounded in empirical evidence. For instance, findings from previous studies can guide the formulation of new research questions.

D. SERENDIPITY AND THE WINDFALL HYPOTHESIS:

◦ Serendipity - an aptitude for making desirable discoveries by accident.
◦ Windfall - an unexpected, unearned, or sudden gain or advantage.

Serendipitous discoveries can lead to significant breakthroughs in research. For example, a researcher accidentally discovering a new effect while testing a different hypothesis can open new avenues for exploration.

E. INTUITION:

◦ “The power or faculty of attaining to direct knowledge or cognition without evident rational thought and inference.”
◦ “Good hunches are really an unconscious result of our own expertise in an area. The more we know about a topic, the better our intuitive hypotheses are likely to be.”

Intuition can guide researchers in developing hypotheses based on their expertise. For instance, an experienced educator might intuitively hypothesize that interactive lessons improve student engagement.

F. WHEN ALL ELSE FAILS:

◦ Read certain topics that might interest you (e.g., library, journals, articles).
◦ Observe those behaviors or events in a natural setting and try to determine their cause.

Exploring various resources and observations can spark new research ideas. For example, reading recent studies on educational methods may inspire a new hypothesis related to student learning outcomes.

V. SEARCHING THE RESEARCH LITERATURE

A. Getting Started:

◦ Focus only on literature relevant to your research hypothesis.
◦ Meta-analysis - statistical reviewing procedure that used data from many similar studies to summarize research findings about individual topics.
◦ Skip popular books written by nonresearchers, essays, and sources from popular media, such as popular magazines and newspapers.

Focusing on relevant literature ensures efficient and effective research. For instance, conducting a meta-analysis can provide comprehensive insights into a specific topic by synthesizing findings from multiple studies.

VI. REFERENCES

◦ Myers A., & Hansen C. (2012). Experimental Psychology (Seventh Edition). Cengage Learning.

Citing references is essential for academic integrity and supporting research findings. For example, referencing established texts provides credibility to new research claims.