The Effect of Protest Zeros on Estimates of Willingness to Pay in Healthcare Contingent Valuation Analysis
Abstract'Protest zeros' occur when respondents reject some aspect of the contingent valuation (CV) market scenario by reporting a zero value even though they place a positive value on the amenity being valued. This is inevitable even in the best-designed CV study, and, when excluded on an ad hoc basis, may cause a selection bias problem. This could affect the reliability of the willingness to pay (WTP) estimates obtained for preference assessment. Treatment of 'protest zeros' in general, and particularly in the context of developing countries, has been rather unsatisfactory. Most case studies employ the Heckman 2-step approach, which is much less robust to co-linearity problems than the Full Information Maximum Likelihood (FIML) estimator. The main objective of this article is to illustrate a sequential procedure to simultaneously deal with co-linearity and selectivity bias resulting from excluding 'protest zeros' in CV analysis. The sequential procedure involves different levels of estimation and diagnostics with the 2-step and FIML estimators; the duration of the procedure depends on the diagnostic test results at each stage of the estimations. The data used for the analysis were elicited using the conventional dichotomous choice buttressed with an open-ended follow-up question. The survey was designed to elicit households' WTP for a proposed community-based malaria control scheme in rural Cameroon. In the application context, we found that the different levels of estimation and diagnostics resulted in reliable WTP estimates from the FIML approach, which would obviously have been overlooked in the absence of such diagnostics.
Download InfoIf you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.
As the access to this document is restricted, you may want to look for a different version under "Related research" (further below) or search for a different version of it.
Bibliographic InfoArticle provided by Springer Healthcare | Adis in its journal Applied Health Economics and Health Policy.
Volume (Year): 8 (2010)
Issue (Month): 4 ()
Contact details of provider:
Web page: http://healtheconomics.adisonline.com/
Contingent-valuation; Malaria; prevention; Willingness-to-pay.;
Find related papers by JEL classification:
- C - Mathematical and Quantitative Methods
- D - Microeconomics
- I - Health, Education, and Welfare
- Z - Other Special Topics
- I1 - Health, Education, and Welfare - - Health
- I19 - Health, Education, and Welfare - - Health - - - Other
- I18 - Health, Education, and Welfare - - Health - - - Government Policy; Regulation; Public Health
- I11 - Health, Education, and Welfare - - Health - - - Analysis of Health Care Markets
You can help add them by filling out this form.
CitEc Project, subscribe to its RSS feed for this item.
- Pedersen, Line Bjørnskov & Gyrd-Hansen, Dorte & Kjær, Trine, 2011. "The influence of information and private versus public provision on preferences for screening for prostate cancer: A willingness-to-pay study," Health Policy, Elsevier, vol. 101(3), pages 277-289, August.
- Brouwer, Roy & Martín-Ortega, Julia, 2012. "Modeling self-censoring of polluter pays protest votes in stated preference research to support resource damage estimations in environmental liability," Resource and Energy Economics, Elsevier, vol. 34(1), pages 151-166.
- Lava Prakash Yadav & Stephen O’Neill & Tom van Rensburg, 2013. "Economic Crisis and the Restructuring of Wage Setting Mechanisms for Vulnerable Workers in Ireland," The Economic and Social Review, Economic and Social Studies, vol. 44(2), pages 221-245.
- Nathalie Havet & Magali Morelle & Raphaël Remonnay & Marie-Odile Carrere, 2012. "Cancer patients’ willingness to pay for blood transfusions at home: results from a contingent valuation study in a French cancer network," The European Journal of Health Economics, Springer, vol. 13(3), pages 289-300, June.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Dave Dustin).
If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.
If references are entirely missing, you can add them using this form.
If the full references list an item that is present in RePEc, but the system did not link to it, you can help with this form.
If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your profile, as there may be some citations waiting for confirmation.
Please note that corrections may take a couple of weeks to filter through the various RePEc services.