| Abstract: | The study evaluated the comparative reliability of different question formats of contingent valuation method by resurvey of the same households nine months after their original survey. The test-retest correlations are statistically significant at 1% level. Comparative reliability of different question formats has been tested comparing the test-retest correlations of these methods. This test has revealed that there is no significant difference in the test-retest correlations between the different question formats for either level A (reduction of the concentration of PM10 by 10%) or level B (reduction of the concentration of PM10 by 20%) air quality improvement. |
