Introduction to Web Surveys. Survey Research Laboratory University of Illinois at Chicago October 2010

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1 Introduction to Web Surveys Survey Research Laboratory University of Illinois at Chicago October 2010

2 Web Surveys First reported use in early 1990 s Dramatic increase in use over the past decade Numerous web survey software packages now available

3 Basic Advantages of Web Surveys Speed Cost Convenient (self-administered) Multi-media delivery (sound, video) Power of computer-assisted programming Unique, hi-tech Similar arguments were made regarding CATI (in the 1970s) and CAPI (in the 1980s) technologies

7 Typology of Web Surveys With thanks to Mick Couper, University of Michigan Survey Research Center (see: Couper, Web Surveys: A Review of Issues and Approaches. Public Opinion Quarterly 2000; 64: ) Non-probability methods Probability methods

8 Non-probability Methods 1. Polls as entertainment 2. Unrestricted self-selected surveys 3. Volunteer opt-in panels

9 Probability Methods 4. Intercept surveys 5. List-based samples 6. Web option in mixed-mode surveys 7. Pre-recruited panels of internet users 8. Pre-recruited panels of full population

10 Type 1: Entertainment Polls question of the day Intended primarily for entertainment No pretense at science or representativeness Basically harmless so long as audience can distinguish them from real surveys

12 Type 2: Unrestricted self-selected surveys Open invitation on portals, frequently-visited web sites, or dedicated survey sites No access restrictions Ballot-stuffing possible Equivalent of poll or magazine insert survey Main distinction with type 1 are claims to legitimacy are sometimes made here

14 Type 3: Volunteer panels of internet users Create volunteer (opt-in) panel using open invitation, recruit large number of people willing to do web surveys Use quota controls or random sampling of select persons from this group for a particular survey Control access through invitation & PIN Although 2 nd step (selection within panel) is controlled, 1 st step is self-selected and uncontrolled

15 Type 3: Continued Claims to generalize to total population Maybe most common approach to web surveys now As with all panels, some of these pay respondents to participate Some are claiming that these panels are equal or better than other forms of data collection based on probability methods

18 Probability-Based Methods #4: Intercept Surveys Target is visitors to a web site Customer satisfaction Web site evaluation Systematic sample commonly used every nth visitor No coverage problem because the population of interest is active web users Biggest problem is nonresponse Also problem of timing when to intercept?

21 #5: List-Based Samples of High- Coverage populations Recruit and invite those with web access to participate Restricted to current internet users Controlled access Nonresponse occurs at many stages in the process but can be measured (via analyses of baseline data) High coverage population examples: College students Members of professional organizations IT professionals

23 #6: Mixed-Mode Designs with Choice of Completion Method Web survey as part of a mixed mode design Example: mail survey with invitation to do via web Requires controlled access Concerns over equivalence of measurement mode effects More expensive than single mode survey Offering respondents a choice helps confront nonresponse problems

25 #7: Pre-recruited Panels of Internet Users Random probability methods used to contact and invite persons with internet access to participate This approach is limited to active internet users More expensive than some other approaches May be difficult to assess nonresponse

26 #8: Probability Samples of Full Population Start with probability sample of target population Give everyone access to internet in exchange for participation Only approach with potential to be representative of general population Biases and errors can be measured Nonresponse, panel effects and costs are big concerns Example: Knowledge Networks

28 Designing Web Questionnaires

29 Basic Design Approaches Static web questionnaire Survey in single HTML document Respondents can scroll through document Data sent to server once when survey is completed Interactive web questionnaire Questions are delivered one at a time or in modules Data is sent to server after each screen is completed Conducive to use of skip patterns, consistency checks, range checks, etc.

30 Static Web Questionnaires Very similar to mail and other selfadministered questionnaires Can minimize download time Respondents can skip questions, but the process is not usually automated Hypertext links can be used to facilitate skips All information is lost if respondent quits before finishing More advantageous for short questionnaires

31 Interactive Web Questionnaires This approach permits the use of all computer-assisted programming devices May increase length of survey due to additional download time Partial data is captured for respondents who quit before finishing questionnaire More advantageous for longer and more complex questionnaires

32 Progress Indicators The purpose is to motivate respondents to complete the questionnaire in the absence of an interviewer Couper et al. (2001): 89.9% completed survey with progress indicator vs. 86.4% completing survey without one Very useful in interactive questionnaires, where respondent does not know how long the questionnaire is Not necessary in static questionnaires where respondents can determine the length by scrolling through it May add to survey length if increase download time There is some concern of increased break-offs Transition sentences are an alternative Empirical evidence regarding effectiveness not clear

39 General Screen Design Do not use background color or images Background colors can create contrast & reading problems visual noise

41 General Screen Design #2 Be aware that images may bias responses Witte et al (2004) National Geographic Survey Images increased support for species protection Couper et al (2007) healthy vs. sick person image When exposed to fit person, respondents consistently rated their own health as lower than when exposed to sick person Use upper right corner for contact information Privacy/IRB information can be clickable from there If top of screen format is consistent: Respondents will tend to ignore that section across pages Banner-Blindness

42 General Screen Design #3 Access to other relevant information can also be provided: Answers to commonly asked questions about the survey pdf versions of the full questionnaire

47 Effect of Color on Web Survey Completion Do not overuse color but use it consistently Use red only for emergency messages Red-green distinctions a problem with persons who are color-blind 10% of males are color blind 99% of color blind persons cannot distinguish green & red White or off-white backgrounds seem to work best Some evidence that R s view black-on-white web pages as being more professional than white-onblack web pages Couper (2008) prefers light blue backgrounds

48 Color, continued For maximum readability, should be high contrast between text color and background color Bright colors are easier to see than pastels Colored backgrounds often used by spammers and may reduce response rates

49 Text Always avoid small font sizes (use point) Appears to be some preference for Arial over Times Roman font Do not overuse bold, underline, italics and other forms of emphasis

50 Question Presentation Avoid requiring R to horizontally scroll Avoid any scrolling may be best

52 Question Presentation Avoid requiring R to horizontally scroll Avoid any scrolling may be best No agreement about inclusion of question numbers Excluding them may avoid skip logic confusion Likert questions (fully-labeled) should be displayed vertically

54 Question Presentation #2 Respondents less likely to skip words when lines are kept short Provide computer-operating instructions at the precise point when a R may need to use that information When # of responses cannot be fitted on single screen: Double- or triple-banking may be best approach Place a box around the categories in order to group them as being relevant to the question

57 Question Presentation #3 Visibility principle Options that are visible are more likely to be selected than those that are not visible until the R takes some action to display them Response models Serial processing model Search options for pre-existing judgment Deadline processing model Spend certain amount of time and select best answer found before cognitive deadline (a form of satisficing)

58 Common Types of Response Options for Web Surveys 1. Radio buttons or boxes 2. Drop-down boxes 3. Check boxes 4. Slider bars 5. Text boxes 6. Open-ended questions

59 Radio Buttons Options are typically mutually exclusive

65 Be careful not to use long grids that lose column headings:

68 Boxes instead of buttons

72 Drop-Down Boxes Useful only for closed lists of response options Can be designed to allow for single or multiple choices Options provided must be exhaustive Drop boxes more difficult to use than radio buttons

77 Beware of Scroll Mice Healy (2007) Drop-downs (compared to radio buttons) led to higher item nonresponse and longer response times Respondents using scroll mice to complete the survey were prone to accidentally changing an answer if presented with drop-down questions

78 Check Boxes Unlike radio buttons, multiple choices can be clicked via check boxes

80 Radio Button/Check Box Hybrid

82 Slider Bars (a.k.a. visual analog scale, graphic rating scales, sliders )

85 Slider Bars - Research Random experiment by Bayer & Thomas (2004) of Harris Interactive Slider bars took about twice as long for completion as any other scale type (including semantic differentials, likert, etc) Answering 2 slider bar questions averaged 42.3 seconds, compared to 21.3 seconds for semantic differential questions Couper (2008) says results using slider bars are quite similar to what is obtained from a scale that uses radio buttons

89 Open-ended Questions providing more space encourages respondents to providing more space encourages respondents to provide longer answers

91 Present Single or Multiple Items per Screen? For interactive questionnaires, multiple items per screen: Are completed more quickly by respondents May provide more context Intercorrelations among items are consistently higher when grouped together on one screen (Couper et al. 2001). Also, multiple item screen versions: take less time to complete produce less missing data

92 Survey Navigation A consistent format should be followed Use action buttons that are different from any response input elements such as radio buttons next screen or next question buttons should be on all pages Crawford et al (2005) recommends putting them in the lower left corner previous screen or previous question buttons should be in the bottom right corner

94 Key Point Never force respondents to answer a question Adds to frustration IRB implications No other questionnaire formats force answers

95 Key Questionnaire Design Principles Summary Minimize respondent burden and frustration The fewer clicks, the better The less scrolling, the better The fewer distractions, the better The fewer problems knowing how to navigate the questionnaire, the better The less download time required, the better Never forcing respondents to answer questions

96 Some other design recommendations to consider (from Couper 2008): Remove unneeded content and clutter Minimize the number of different colors and fonts being used Use consistent design formats through the entire instrument Avoid putting too much material on any page

97 Summary Web surveys vary greatly in their goals, design, execution, analysis, etc. Evaluation must be done in the context of the type of survey being conducted Cannot say that all web surveys are good or bad Methodological research is being done on a moving target

98 Thank You

2/28/2011. Web Surveys. Introduction to Web Surveys. Basic Advantages of Web Surveys

2/28/2011. Web Surveys. Introduction to Web Surveys. Basic Advantages of Web Surveys Web Surveys Introduction to Web Surveys Timothy Johnson Survey Research Laboratory University of Illinois at Chicago March 2011 First reported use in early 1990 s Dramatic increase in use over the past