Research Methods Tutorial American River College Instructor: Lori hokerson, M.A. Last updated on January 21, 2008

Student Objectives By the end of this lesson, students should be able to: Elaborate on the 4 goals of the scientific method. Explain each step of the scientific method. Differentiate between descriptive and experimental methods. Assess the relevance of statistical analysis.

Instructions This is an interactive tutorial. Please follow the instructions on each slide. Click on hyperlinks first, then on the arrows.

The Scientific Method Why use the scientific method? What are its’ assumptions? How does it work? To find out answers to the questions above, click on each link. Then click on the arrow in the top corner to continue.

Why use the scientific method? There are 4 goals: Describe Explain Predict Control A study reported that babies and infants that watch programs geared toward enhancing intelligence have fewer words than their non-program watching cohorts.. A study reported that childhood sexual abuse is correlated with prostitution in females. A longitudinal study reported that factors such as motivation, creativity, and willingness to work hard are predictors of academic success. A study reported that antidepressant use by adolescents can increase the risk of suicide.

What are its’ assumptions? All events are lawful… …therefore… …behavior and mental processes follow consistent patterns. hence, all events can be explained. In the absence of these assumptions, it would be impossible to achieve any of the 4 goals of science.

How does it work? The Scientific Method Step 1: Formulate Step 3: Analyze Step 2: Design Step 4: Report

Step 1: Formulate The Scientific Method 1. What is your hypothesis? 2. What variables are you going to study? 3. How are you going to operationalize them? 4. Are your variables observable and measurable?

The Hypothesis Step 1: Formulate a statement about the possible relationship between two or more variables Childhood Intelligence and Success. These are the variables that are going to be studied. What do you think the relationship between these variables might be? The hypothesis describes the nature of the relationship that you predict between these variables. For example, childhood intelligence will be a predictor of success . But to be more specific… High childhood intelligence will predict success in school and employment.

How to Operationalize Variables Step 1: Formulate Do you like fruit? Seems like a simple question, but it’s not quite clear. If you like apples, but not bananas, you wouldn’t be able to answer this question without additional clarification. Thus if I rephrased the question, “Do you like apples?” You could give a clear response. This rephrasing illustrates the process of operationalizing variables.

Operationalized Example Step 1: Formulate A researcher wants to evaluate the long-term effects of highly intelligent children. Hypothesis: Children with high intelligence will be successful. Variables: Can you identify the variables in this hypothesis? Now they need to be operationalized. High Intelligence: IQ as it is measured by the Weschler Intelligence Scale for Children (WISC). Successful: Measured by the number of years in higher education and salary in employment.

Step 2: Design The Scientific Method Who is being studied? Demographics – characteristics of the subjects (e.g. gender, ethnicity, age, socioeconomics) Recruitment – method by which subjects volunteered for the study (e.g. mailed surveys, college, treatment center) Why is it important to know this information? So that the results can be easily understood.

Examples Step 2: Design How old were the babies & infants? Is this true for both boys and girls? Did these subjects have working parents? Is this true for persons of different ethnicities? A study reported that babies and infants that watch programs geared toward enhancing intelligence have fewer words than their non-program watching cohorts.

The Design Step 2: Design Choosing A method Experimental vs. Descriptive Attempts to explain a cause-and-effect relationship between variables. Independent Variable Dependent Variable Control Group Experimental Group Attempts to describe any relationship between variables. Surveys Case Studies Interviews Observational

Step 3: Analyze The Scientific Method Statistics allow for conclusions to be drawn, but first the data has to be analyzed. (click on the links below, then click on the arrow above to return to the 4 steps) Statistical Significance Correlations Raw data must be turned into meaningful data then interpreted.

Statistical Significance Step 3: Analyze Statistical significance allows for researchers to conclude that without a doubt, there is (or isn’t) a causal relationship between variables. Because of this, statistical significance is highly important when using experimental method. When reporting significance, researchers choose a threshold, such as .05 or .01. When significance meets these thresholds, it can be said that without a doubt, variable X produced a change in variable Y. However, if the significance threshold is not met, then the null hypothesis is supported.

Correlations Step 3: Analyze Correlations describe the nature of the relationship between variables. There are 2 types of correlations (click on each): Positive Correlations Negative Correlations

Positive Correlations As one variable increases, so does the other. The chart to the right shows that as IQ score increases, so does average salary . ----OR----- As one variable decreases, so does the other. The Chart to the right shows that as levels of stress decrease, so do the number of altercations with a spouse. Note that the positive correlation does not conclude a causal relationship.

Negative Correlations As one variable increases, the other. variable decreases The chart to the right shows that as the number of hours in therapy increases, the occurrence of ADHD symptoms decreases. In the chart to the right, as hours spent watching TV increases, number of retained vocabulary decreases. Note that the negative correlation does not conclude a causal relationship.

If you discovered a vaccine for cancer, would you keep it to yourself? Step 4: Report If you discovered a vaccine for cancer, would you keep it to yourself? Reporting the results of a study allow for the 4 goals to be achieved. It also allows for others to attempt to replicate its findings, which increases its reliability. All psychological studies are reported using American Psychiatric Association (APA) format and are published in professional journal articles.

The scientific method is the foundation for much of psychology. In Conclusion… The scientific method is the foundation for much of psychology. It allows us to describe how variables relate, or don’t relate. It allows us to conclude when one variable causes another. It allows us to generalize the results of a small study to a much larger population. It allows us to replicate findings in future studies. The End