Concepts Concepts 10 28 2013 Building blocks of theories Abstractives that describe portions of reality General name for specific instances of a phenomenon being described o E g mass media use an abstract concept that encompasses many different individual activities Most abstract construct o Construct may be used with concept Variables Variable a measurable version of a concept or construct that can take on two or more values able to vary Value some attribute category or quantity of a variable A nonvariable cannot be broken down into smaller parts Variability and relationship For a relationship between two concepts to exist each must be a Must define concepts so that they each encompass multiple values variable and There needs to be variability in the data no variables action as nonvariables Independent Variable Dependent Variable Independent and dependent variables refer to variables in causal hypotheses X is independent of Y Time is always independent Most statistical procedures do not provide evidence for a causal direction only evidence that a relationship is likely to exist Causal relationship Requirements A relationship must exist covariation Changes in the independent variable must come before changes in the dependent variable time order Alternative explanations must be ruled out lack of spurious relationships Levels of measurement Numerical o Categorical discrete o Continuous How much information o Nominal name based o Ordinal senior o Interval o Ratio Dimensions There is an order i e freshman sophomore junior A concept is multidimensional if it has more than one aspect to it that are each free to vary somewhat independently Dimensions are the different facets of a complex construct sometimes also called factors Differences in dimensions may underlie what appear to be discrete categories Media type Monthly magazine Weekly magazine newspaper Daily newspaper TV network news Radio news 24 hour cable news Internet news Example Personality Big Five Personality Theory o Openness o Conscientiousness o Extraversion o Agreeableness o Neuroticism Myers Briggs Type Indicator o Extraversion introversion o Sensing intuition o Thinking feeling o Judging perception What makes it a dimension Media use o Dimension 1 media exposure Variable 1a days week of use for each medium Variable 1b min day of use for each medium Variable 1c number of media used o Dimension 2 content type Variable 2a amount of attention to each type Variable 2b frequency of exposure to each type o Dimension 3 media functions Variable 3a extent to which person is information Variable 3b how successful each medium is in fulfilling seeking this function Indicators Definitions Ways of measuring a concept o Scales indexes o Variables Theoretical definition conceptual definition conveys the meaning we attach to the concept and may suggest indicators of it Operational definition complete and explicit information about how to measure a concept how we define it for the purposes of the current study or operationalize the concept Validity How well the indicators operational definition captures the construct theoretical definition How much of the meaning space is covered by the measurements The actual text of a survey question and the type of response it Survey Operationalizations solicits Open ended response o Text what is your favorite TV genre o Numerical how many days per week Multiple choice Scaled response o Which of the following is your favorite TV genre list options o Likert scale rate on a scale 1 to 7 o Semantic differential good bad Experiment Operationalizations Manipulated variables IVs the two or more different conditions that the participants are exposed to in order to test an effect e g assigning children to watch either a violent or non violent show Measures variables DVs and control variables o Questionnaire questions as in surveys o Measurements from computers or tools such as stopwatches scales rulers o Physiological measurements such as heart rate EEG fMRI etc o Observational data coded Content Analysis Operationalizations Content variables o Specific code scheme developed to identify classify content Noncontent variables measures as in other types of research Concepts vs Measures Theoretical Statements 10 28 2013 Statement about the value of or relationship between variable s Drawing Concepts Measures Ovals concepts Arrows linkages Boxes measures Theoretical statements o Hypothesis o Assumption o Proposition o Postulate o Theorem o Axiom Hypothesis variables Proposition A testable statement about the relationship between two or more A statement about the value of a single variable o Often not very useful o Can take on normative tone o Can include hidden assumptions or implicit comparisons should be converted to hypotheses o E g the free flow of information is valuable in a democracy Assumptions An untested and possibly unstated idea about the value of or relationship between concepts variables o May be untested because it s beyond the scope of the study o May be untestable o Can be propositional or relational o Should be identified and stated when possible beware of everybody knows Measuring undergraduates who participate for course credit is a valid way of studying people in general The way that people behave in a laboratory is identical to the way People can and do accurately answer questions about their they behave in their lives cognitions and behavior Men are more motivated to succeed in the workforce than women are or he will make Women are better at caring for others than men are The more information a decision maker has the better decision she Might be the rationale for hypotheses theoretical linkages Might underlie categories of a categorical variable o Gender sex spatial ability video game ability I dimension o Media type frequency of updating AND saturation use for information seeking 2 dimensions Theoretical Statements Relating Two Variables 10 28 2013 Theory Project Can modify existing theory base your ideo on an existing theory o MUST CITE existing theory articles or book chapters NOT textbooks o Must introduce some new element e g new context that generates NEW relationships hypotheses Covering Laws theories designed to be studied empirically will be best suited to the book and the rest of the course Focus on concepts and relationships Recognized your limits 10 12 minutes 8 10 pages is not a lot for explaining a theory Forms of hypothesis Difference involves at least one categorical