1. wed, jan 27, 2015 using large data sets

2. today’s line-up… Survey research as a method General Social Survey GSS (dataset for our project) Project details, variables, think about groups SPSS & UNC Virtual Lab Example of project presentation

3. What is a survey? A survey is:

4. What is a survey? A survey is: – a systematic method for gathering information – from (a sample of) entities – for the purposes of constructing quantitative descriptors – of the attributes of the larger population of which the entities are members

5. typically, surveys… Gather information by asking people questions Collect information by either (1) interviewers asking questions and recording responses or (2) respondents reading and recording their own answers Collect information from a subset of the population, a sample, rather than from all members

6. Polls vs. Surveys No clear distinction between the two terms – “Poll” often used for private sector opinion studies Use many of the same design features as studies that would be called surveys – “Poll” rarely used to describe government or scientific surveys To me, the term poll implies either – A commercial or less-scientific study, or – A quick turn-around survey whose results may be of short- term interest

8. The SAGE Handbook of Online Research Methods (2008) Based on probability design* *units are selected using a method that ensures that each unit has a known, nonzero probability of being included

9. 1936 election and the Literary Digest survey Magazine had predicted every election since 1916 Sent out 10 million surveys---and 2.4 million responded They said: Landon would win 57% of the vote What happened: 62% Roosevelt landslide

10. What went wrong? Sample not representative Lists came from subscriptions, phone directories, club members Phones were a luxury in 1936 Selection Bias toward the rich Voluntary response: Republicans were angry and more likely to respond Context: Great Depression – 9 million unemployed – Real income down 33% – Massive discontent, strike waves

11. Steps in conducting a survey Clearly state research objective(s) Decide on survey mode(s) – How will you contact potential respondents? (web, email, phone, etc.) – In what media will the survey be given? (web, email, phone, etc.) Determine fielding strategy (how to maximize response rates?) Design the survey questions and the survey instrument

12. Determine sample size and sampling strategy Obtain Institutional Review Board (IRB) or other approval as necessary – Are respondents promised confidentiality? – What is the impact if their survey responses become known? Pre-test – Give the survey to some test subjects and get their feedback What works and what doesn’t? Are you getting correct data/information? – Revise and re-pre-test as necessary Steps in conducting a survey

15. General Social Survey The GSS (General Social Survey) is a biannual personal interview survey of U.S. households conducted by the National Opinion Research Center (NORC). The first survey took place in 1972. Approximately 3000 American adults are interviewed in person for about 90 minutes and asked around 450 questions.

16. http://www3.norc.org/gss+website/

17. Purpose of GSS gather data on contemporary American society in order to monitor and explain trends and constants in attitudes, behaviors, and attributes over time to compare the United States to other societies

18. General Social Survey demographics & attitudes – The questionnaire contains a standard core of demographic and attitudinal variables, plus certain topics of special interest selected for rotation (called "topical modules") – Items include national spending priorities, drinking behavior, marijuana use, crime and punishment, race relations, quality of life, confidence in institutions, and membership in voluntary associations

19. Data to Story Project Go over project description Components – Project description – Search log – Annotated bibliography – Presentation [handout] Emphasize that GSS and statistical analysis are just the topical launch point; substance of project is in information search/retrieval, info analysis and info presentation

20. Get into the GSS dataset… 1.Download the dataset onto your computer or flashdrive – Go to class schedule for Jan 27 http://ils.unc.edu/courses/2016_spring/inls151_002/schedule. html http://ils.unc.edu/courses/2016_spring/inls151_002/schedule. html – Right click on GSS 2014 Dataset to SAVE AS on your computer (file called “GSS2014.INLS151.sav”) 2.Log into the UNC Virtual Lab https://virtuallab.unc.eduhttps://virtuallab.unc.edu 3.On the left under “Statistics”, select SPSS 4.Once the SPSS program opens, drill down to your computer to find the GSS2014.INLS151.SAV file to open the GSS dataset

22. variables variable – a characteristic that can vary in value among subjects in a sample or a population. We are interested in similarities and differences - variance types of variables – categorical – quantitative

23. categorical variable scale for measurement is a set of categories examples: – Racial-ethnic group (white, black, Hispanic) – Political party identification (Dem., Repub., Indep.) – Vegetarian? (yes, no) – Mental health evaluation (well, mild symptom formation, moderate symptom formation, impaired) – Happiness (very happy, pretty happy, not too happy) – Religious affiliation – Major

24. SPANKING: Categorical (Single) Do you strongly agree, agree, disagree, or strongly disagree that it is sometimes necessary to discipline a child with a good, hard spanking? Categories: Code as: {strongly_agree} Strongly agree 5 {agree} Agree 4 {disagree} Disagree 3 {strongly_disagree} Strongly disagree 2 {dontknow} DON'T KNOW 1 {refused} REFUSED 0 Sample question from GSS

25. scales of measurement for categorical variables, two types:  nominal scale – unordered categories o preference for president, race, gender, religious affiliation, major opinion items (favor vs. oppose, yes vs. no)  ordinal scale – ordered categories o political ideology (very liberal, liberal, moderate, conservative, very conservative) o anxiety, stress, self esteem (high, medium, low) o mental impairment (none, mild, moderate, severe) o government spending on environment (up, same, down)

26. PRES12: Categorical (Single) Did you vote for Obama or Romney? Categories: Code as: Obama5 Romney4 Other Candidate (Specify)3 Didn’t vote for president2 Don’t know1 Refused0 nominal scale – unordered categories

27. POLVIEWS: Categorical (Single) We hear a lot of talk these days about liberals and conservatives. I'm going to show you a seven-point scale on which the political views that people might hold are arranged from extremely liberal--point 1—to extremely conservative--point 7. Where would you place yourself on this scale? Categories: Code as: Extremely liberal 7 Liberal 6 Slightly liberal 5 Moderate, middle of the road 4 Slightly conservative 3 Conservative 2 Extremely conservative 1 DON'T KNOW 0 REFUSED 8 ordinal scale – ordered categories

28. quantitative variable possible values differ in magnitude examples: – Age, height – Annual income – Time spent on online each week – Reaction time to a stimulus – (e.g., cell phone while driving in experiment) – Number of “life events” in past year

29. statistics descriptiveinferential hypothesis testing estimation

30. descriptive statistics frequency distribution measures of central tendency modemedian mean use of statistics to describe, summarize, and explain or make sense of a given set of data

31. Mean – Uses all of the data – Has desirable statistical properties – Affected by extreme high or low values (outliers – example*) – May not best characterize skewed distributions Median – Not affected by outliers – May better characterize skewed distributions Comparison of mean and median *UNC Geography Majors Salaries Example

32. mid-1980's at the University of North Carolina, the average starting salary of geography students was well over $100,000

33. CorrelationCausation

34. sample patterns from GSS data – median income of female respondents compared with average income of male respondents – median level of education of respondents who own a gun – number of female respondents who own a gun compared with number of male respondents who own a gun – average age of respondents who indicated the government should spend more on space exploration – self-reported level of happiness compared with income level

35. sample characteristics of the GSS The sampling frame of the General Social Survey is all U.S. adults living in households. The sampling frame includes 97.3 % of all U.S. adults. Who does not live in a household? – college students in dorms – military personnel in barracks – prisoners – elderly persons in retirement homes

36. Does the GSS sample really draw from all the adults in its sample frame? After the GSS is sampled, only 70% of persons in the sample actually respond to the survey – 23% refuse or cut the survey off in the middle – 2% are unavailable or can’t be found – 5% are missing for other reasons In general, a response rate of 60% or more is considered minimally acceptable, but you should check your results in any way you can.

37. You can look at actual GSS questionnaires http://www3.norc.org/gss+website/

38. where can you access SPSS? Odum Institute – Davis Library 2 nd floor – ask lab assistant https://virtuallab.unc.edu Lab in the Undergraduate Library (need to confirm)

39. Sample project from previous class…

40. Notes… Bring a flash drive to the Odum lab on Monday – you may want to save your work Davis Library >> Room 219 The dataset that we are using (GSS 20124) is available for download on our class website – schedule>>Jan 27 – the dataset is a.sav format – only opens with SPSS

41. Homework #1: Analyzing a research article Select one of the seven research articles linked from our class schedule (listed under readings for Jan 25) Using the Analyzing Research Articles handout (also listed under Jan 25, need one?), critique the article Focus on the purpose of the study, description of study design (participants, methods, how they collected data), data analysis and conclusions Don’t worry about specific statistical analysis methods Due Mon, Feb 8– print or email to me by class time Format – whatever works for you (bullets, address some but not necessarily all questions/points from handout) Worth up to 3 points (out of 100)

42. Rationale for assignment Use evaluative strategies and vocabulary to examine a scholarly research product – (the “analyzing information” part of our class title) Explore research that has been conducted using the same dataset that we will be using for our project, the General Social Survey