Randomized response approach to sensitive issues in surveys

1. Randomized response approach to sensitive issues in surveys S-005 examples

2. The randomized-response strategy:Why try this? • Sensitive questions • Drugs, cheating on tests, sexual behavior, etc. • Some people are reluctant to respond accurately • Sometimes the issues are extrinsic • Illegal, prohibited, etc. • Sometimes intrinsic or personal • Socially desirable or undesirable • Some approaches • Anonymity • Confidentiality • Trust / rapport with researchers • Multiple options or questions • A mix of open-ended and close-ended questions • Others?

3. Randomized response approach Original idea (Warner, 1965) • Use two questions: • The sensitive question and its complement • “Have you ever used drug X?” • “Have you never used drug X?” • Have the respondent determine which question to answer. Roll dice or use a spinner. The interviewer does not decide and does not know which question is chosen. “If the total is eight or less, please answer question 1. If the total is nine or greater, please answer question 2. Do not tell me which question you answer. Please answer truthfully. No one will know which question you are answering.”

4. Randomized response approachVersion 2: The innocuous question • Use the sensitive question and also an unrelated (innocuous or non-sensitive) question. • “Have you ever used drug X?” • “Were you born during January, February, March, April, May or June?” “If you spin a 1 or 2 or 3, please answer question B. Otherwise, please answer question A. Do not tell me which question you answer. Please answer truthfully. No one will know which question you are answering.” Important: We pick the unrelated question so that we will have a very good idea of what percentage will answer “yes.”

5. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

6. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

7. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

8. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

9. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

10. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

11. Some possible results • Example: We try this with 100 people. • 40 people (40%) answer “Yes” • What is our estimate of the percentage of people who really have used Drug X?

12. Some possible results • We estimate how many people will answer question B, and then we are pretty sure how many will answer “Yes” to question B. (In our example, 30 people (30%) will get question B, and then half of them are likely to answer “Yes.”) • Then we can get the other numbers by subtraction. Some of the original “Yes” answers were from people answering question A, but some were from those answering question B.

13. Some possible results • So now out estimate of the percentage of people who have used Drug X is found in the column for Question A. • We know that (about) 70 people answered this question. • 25 of them answered “Yes” • So 25/70 = .357, or 35.7% (about 36%) report using Drug X 36% 64%

14. Randomized response approachVersion 3: The some-say-yes • Use the sensitive question. But randomly tell some people to automatically answer “yes.” “Please flip a coin. If the coin is “heads,” then please give a “yes” answer to the next question. If the coin is “tails,” please answer the question honestly.” The coin flip will mean that at least 50% will answer “yes.” • “Have you ever used drug X?” Yes No

15. Randomized response approachVersion 3 with several questions • Use a series of sensitive questions. Get a coin. Toss the coin three times, and record the results of those tosses (heads or tails) on a sheet of paper. There will be a series of three questions. Answer the first question honestly if the first result was “heads”; or simply answer with “yes” if the result was “tails”. Use the same procedure for each of the questions. Results 1. H T 2. H T 3. H T

16. Now here are the follow-up questions. After the person keeps track of the coin flips, let’s see the answers to a series of questions about sensitive issues. • Have you ever been a victim of cyber-bullying or harassment from a social-networking site? • Have you ever submitted a course assignment (or even part of an assignment) that was not really your own work? • Have you ever taken food that was for a meeting or reception that you were not really planning to attend? ☐Yes ☐No ☐Yes ☐No ☐Yes ☐No • Depending of the result of your 1stcoin toss, please answer the first question honestly if the coin was “heads.” Please give an automatic answer of “yes” if the 1st coin toss was tails. • Depending of the result of your 3rdcoin toss, please answer the third question honestly if the coin was “heads.” Please give an automatic answer of “yes” if the 3rd coin toss was tails. • Depending of the result of your 2ndcoin toss, please answer the second question honestly if the coin was “heads.” Please give an automatic answer of “yes” if the 2nd coin toss was tails.

17. We handle results here just as we did for the earlier methods. • This time we know that half the people will automatically answer “Yes”. (In this example, 50 people (50%) are likely to answer “Yes.”) • As in the earlier example, we can get the other numbers by subtraction. Some of the original “Yes” answers were from people who answered “yes” because of the coin flip, but some were from those who honestly answered “yes.” Example: Have you ever been cyber-bullied? Let’s imagine a total of 60 people said “yes.”

18. But does this really work? • Limitations? • Need to have a spinner or dice or something to allow the random choice (even coins may be a challenge) • Time consuming • Confusing for some people • Annoying for some –interrupts the questions • Feasibility for on-line use? • Self-administered vs. • Does it really help people answer truthfully? • It does provide anonymity • But do people understand the process? • Do they believe the process? • Studies comparing RR methods with direct questioning are a bit mixed. • Some studies show only minor differences • Some analyses seem to show some positive results • I am still skeptical • I like the method of “direct questioning”