Unformatted text preview: Chapter 2 The Research Process: How We Find Things Out The Scientific Method What are the components of the scientific method? Specify a problem Form a hypothesis "People will remember more words from a list of happy words if, while studying, they listen to happy music than if they listen to sad music." "When asked why the do not steal, older children will report considering the consequences but younger children will report they are obeying adults." Systematic observation Read studies already published Collect Data Replication of studies Test the hypothesis Operational definition How can you measure psychological constructs such as... Depression Shyness Formulate a theory Test the theory New studies! The Scientific Method What is the relationship between theory, prediction (a hypothesis), and data?
Prediction Theory Theory development, validation, correction Data Naturalistic observation Case studies Surveys Describing Behavior: The Descriptive Research Methods Predicting Behavior: Correlational Research Studies where the relationships between two or more variables are measured Examples Correlation
Strength and direction Correlation Research Strength Can study variables that cannot be manipulated Weakness Correlation does not imply causation
3rd variable problem directionality Designing Experiments: Independent Variable
The aspect of a situation that is _______________ while another aspect is measured Examples Designing Experiments: Dependent Variable
The aspect of a situation that is ___________ while the independent variable is changed Examples QuickTime. and a TIFF needed to see thisdecompresso are (Uncompressed) picture. Designing Experiments: Effects
The difference in the dependent variable that is due to changes in the independent variable Examples Drug X impairs shortterm memory Visualization improves athletic performance Practice improves reading speed Characteristics of Experiments Experimental group Control group Random assignment Strength Weakness QuasiExperiments Like experiments but without random assignment Examples: Naturallyoccurring groups Bias and Expectation Response bias Sampling bias Experimenter expectancy effects Doubleblind design Design an Experiment State the Problem: Is it more beneficial to read before or after lecture?
Independent Variable: Dependent Variable: Assignment to Groups: Factors to Control: Being a Critical Consumer Reliability Validity Imagine we have a broken thermometer. Four readings on one person are: 98.4, 96.5, 90.1, 99.3 Imagine we have a working thermometer. Reliable? Valid as a measure of illness? Of anger? Statistics: Measuring Reality Be a critical statistics consumer; know the basics Two main types of statistics Descriptive Inferential Descriptive Statistics Central tendency Mean Median Mode Normal distribution Descriptive Statistics Variability Range Standard deviation Inferential Statistics Do patterns in measurement reflect true patterns or just chance variation? Statistical significance A measured relationship is not simply due to chance Expressed in terms of probability (p) Psychologists generally view a finding as "statistically significant" if it has no more than a ___ probability of occurring by chance Inferential Statistics Sampling Population Sample Sampling error Population Sample random assignment! Even with ...
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