1. QUANTITATIVE METHODS I203 Social and Organizational Issues of Information

2. A Problem… Yoogle.com wants to better understand the concept of ‘credibility’ in information. In particular, they want to know more about how their users make judgments about credibility in information. 2

3. 3 (photo courtesy of dailyhaha.com) (Induction) (Deduction)

4. 4 Inductive Logic of Research in Qualitative Studies Generalizations are made, or Theories to Past Experience And Literature Researcher Looks for Broad Patterns, Generalizations, or Theories from Themes or Categories Researcher Analyzes Data to Form Themes Or Categories Researcher Asks Open-Ended Questions of Participants Or Records Field Notes Researcher Gathers Information

5. 5 The Deductive Approach in Typical Quantitative Research Researcher Tests or Verifies a Theory Researcher Tests Hypotheses or Research Questions From the Theory Researcher Defines and Operationalizes Variables Derived from the Theory Researcher Measures or Observes Variables Using an Instrument to Obtain Scores

6. 6 If our goal is to find support (or not) for a theory or hypothesis, how do we establish such a relationship? …and if we do establish a relationship, how do we know?

7. Research types and causality: Descriptive  Descriptive  Summarize data  Statistics: histograms, means, percentages 7

8. Research types and causality: Associational  Associational  Only to relate variables  Predictions only made to show that a relationship exists  This is where test statistics (t, F, Chi-Square) become important, along with the p- value (essentially the probability associated with the statistic)  Statistics: Correlation, Multiple Regression 8

9. Research types and causality: Comparative  Comparative  Compares two or more groups  Looking for difference between groups  Common Statistics: t-tests, ANOVA (inferential statistics) 9

10. Questionnaires, Surveys Experiments and Experimental Designs Common Types of Quantitative Research Methods (Methods of Research) 10

11. Surveys  Method of Analysis  Rely on existing variation in the sample population to obtain a ‘representative sample’.  Surveys also control for the influence of external factors by asking lots of questions from the same people.  Surveys are not the same thing as Questionnaires!  That is, in-depth interviews, observation, content analysis could also be used in survey research.  Questionnaires are a specific method for obtaining a structured set of survey data. 11

12. Potential Problems in Questionnaires and Surveys  Obtaining a representative sample  1930’s Literary Digest poll: Franklin Roosevelt predicted to lose the 1936 presidential election by a landslide. Oops… he won by a landslide.  Accounting for outliers in sample  What is the best undergraduate major if you want a high income (UNC-Chapel Hill survey)? One outlier, a geography major named Michael Jordan, accounted for the huge skew in average salaries for graduates (at the time he made $80 million/year) 12

13. Advantages and Disadvantages of Surveys and Questionnaires  Advantages  Can be easily scaled for small or large studies  Allows researcher to collect a lot of data on a wide range of topics  Disadvantages  Sampling becomes a big issue if you want to generalize to larger population  Most survey data cannot be used for true causal tests However, Longitudinal data can help alleviate this problem (but not completely) 13

14. Experiments 14 Little Albert Milgram’s Authority Experiment

15. What to look for in a Quantitative Study: Conditions of Causality  Covariation  Non-spurious relationship  Logical time ordering  Mechanism to explain how X causes Y 15 XY

16. True Randomized Experimental Design  (1) Independent Variables are manipulated  (usually by experimenter, sometimes by context)  (2) Participants must be assigned randomly to various conditions or groups  When this condition is not met, it is a quasi-experimental design 16

17. 17 Common Experimental Designs R O O XO O R X O O R O O XO O (1) (2) XO(3) O(4) Pretest-Posttest Control Post-only Control Solomon 4-group

18. Experiments  Advantages  Gives researcher tight control over independent factors  Allows researcher to test key relationships with as few confounding factors as possible  Allows for direct causal testing  Disadvantages  Usually a smaller N and number of independent variables than surveys.  Sometimes give up large amounts of generalizability in favor of direct causal analysis and controls.  Require a large amount of planning, training, and time. 18

19. Making Sense of Quantitative Studies  Think about the sample, who does this represent?  Read the ‘Methods’ section…how did they create their measures? Do you believe that the measures represent the intended concept(s)?  What are the potential confounding variables?  Think about the generalizability of the study.  Think about whether the analysis is claiming to be a test of causality (what was the method? How is causality established)?  Interpretation matters just as much in a quantitative study as a qualitative study!

20. Mixed Methodologies Win  Puts the emphasis on the problem, not the method  Many combinations found in broad range of research topics: Experiment / Questionnaires Field Study / Experiment Interviews / Questionnaires Participant Observation / Experiments  Can also include using both qualitative and quantitative methods of measurement in a single study.

21. Assignment 1 21