Research Methods in Abnormal Psychology
● Scientific method
○ A basic series of steps designed to obtain and evaluate, in a systematic way,
information relevant to a problem
○ Essence of the scientific method is objectivity: the process of testing ideas about
the nature of psychological phenomena without bias before accepting these
ideas as adequate explanations
○ Select & Define a problem (relationship between stress and depression)
○ Establish hypothesis or testable statement of predictions for study
○ Choose method
○ Collect and/or analyze data
○ Conclusions- research report
○ Hypothesis:
■ A testable prediction of what you predict will happen in your study
■ Informed by research
● What kind of evidence would support the idea that stress causes
depression?
○ Null hypothesis
■ The prediction that there is no relationship between the variables studied.
■ No relationship between stress and depression
■ Results often support the null hypothesis
■ Must know this for quiz, how to explain relationship and if there is not one
○ Choosing and implementing a method
■ A variable is a factor or characteristic that can vary within an individual(s).
Weight, mood, and attitude
■ Independent variable (IV): stress
● The factor we believe will affect the dependent variable.
● The variable whose level is adjusted or controlled by the
experimenter
■ Dependent Variable (DV): depression
● Variable we are trying to predict
● The variable whose value is the outcome of the experimenter’s
manipulation of the independent variable
■ Operationalization
● Refers to the way variables are measured, defined, and
manipulated
○ Selecting a sample
■ A critical choice in a correlational study is the choice of the sample. A
sample is a group of people taken from the population we want to study
■ A representative sample is a sample that is highly similar to the
population of interest in terms of sex, ethnicity, age, and other
important variables
■ If a sample is not representative- for example, if there are fewer women
or people of color in our sample than in the general population of interest-
● Scientific method
○ A basic series of steps designed to obtain and evaluate, in a systematic way,
information relevant to a problem
○ Essence of the scientific method is objectivity: the process of testing ideas about
the nature of psychological phenomena without bias before accepting these
ideas as adequate explanations
○ Select & Define a problem (relationship between stress and depression)
○ Establish hypothesis or testable statement of predictions for study
○ Choose method
○ Collect and/or analyze data
○ Conclusions- research report
○ Hypothesis:
■ A testable prediction of what you predict will happen in your study
■ Informed by research
● What kind of evidence would support the idea that stress causes
depression?
○ Null hypothesis
■ The prediction that there is no relationship between the variables studied.
■ No relationship between stress and depression
■ Results often support the null hypothesis
■ Must know this for quiz, how to explain relationship and if there is not one
○ Choosing and implementing a method
■ A variable is a factor or characteristic that can vary within an individual(s).
Weight, mood, and attitude
■ Independent variable (IV): stress
● The factor we believe will affect the dependent variable.
● The variable whose level is adjusted or controlled by the
experimenter
■ Dependent Variable (DV): depression
● Variable we are trying to predict
● The variable whose value is the outcome of the experimenter’s
manipulation of the independent variable
■ Operationalization
● Refers to the way variables are measured, defined, and
manipulated
○ Selecting a sample
■ A critical choice in a correlational study is the choice of the sample. A
sample is a group of people taken from the population we want to study
■ A representative sample is a sample that is highly similar to the
population of interest in terms of sex, ethnicity, age, and other
important variables
■ If a sample is not representative- for example, if there are fewer women
or people of color in our sample than in the general population of interest-
