1. Green public choice & OR- A case of solid waste disposal improvement & preference in Malaysia
Chuen-Khee PEK, Nottingham University Business School Malaysia
Jamal Othman, National University of Malaysia

2. Presentation flow
Background and objectives (initial & extended) of study
Methods
Results and discussion
Conclusion

3. Background and objectives
siting of noxious solid waste disposal (SWD) facilities is no longer only an engineering issue- but also involving social tradeoffs
hence, the obective of the initial study was to identify if the users are willing-to-pay for improved SWD technologies vis-a-vis the status quo
an economic analysis was performed on the household demand for municipal SWD service improvements by estimating the implicit prices of disposal service attributes

4. Background and objectives (2)
disposal service attributes- psychological fear (anxiety), land use, air pollution, and river water quality
In determining the economic value of disposal services, an important basic study component was to identify the influence of specific disposal technology labeling (relative to generic technology)

5. Background and objectives (3)
the initial results revealed that the users were WTP but did not address which is the improved technology that was preferred
hence, the extended objective addresses this hidden preference
this gives policy makers a clearer understanding of the demand for improved facilities

6. Methods
choice experiment analysis- 873 heads of urban households who were users of SWD services in the sub-district of Broga, Malaysia
423- generic-format questionnaire, and 450-technology-specific questionnaire
first part of the paper utilised three indirect utility functions for the multinomial logit (MNL) models, each representing the respective resource use option

7. Methods (2) Generic form Option 1: status quo
Options 2 and 3: improved plans with better environmental attributes
Label-specific form
Controlled tipping: status quo
Sanitary landfill and incineration: improved pans with better environmental attributes

8. Methods (3)
The utility of each function was : Vi = C0 + β1*PSYF + β2*LAND + β3*AIRP + β4*RWQL + β5*ADPY for i = 1, 2, and 3 and C0 = 1 for i = 1

9. Methods (4)
The MNL model was extended to incorporate socioeconomic and attitudinal variables by applying the following equation: Vi = C0 + γ1C0*PROEX + γ2C0*AGE + γ3C0*RESD + γ4C0*KIDS + γ5C0*RACE + γ6C0*GDR + γ7C0*CARE + γ8C0*MBR + γ9C0*OWNHSE + γ10C0*QUAL + γ11C0*HHINC + γ12C0*STPROF + γ12C0*TYPROF + γ13C0*DEMO + β1*PSYF + β2*LAND + β3*AIRP + β4*RWQL + β5*ADPY for i = 1, 2, and 3, and C0 = 1 for i = 1

10. Results and discussion
for the initial objective, only one ASCC (i.e. C0) was utilised in the regression model because the concern was with comparing the improved, yet labelled, technologies in aggregate with the status quo
in contrast, for the extended objective, a specific ASC was assigned to the sanitary landfill (i.e. ASCS) and to the incinerator (i.e. ASCI), as individual alternatives to controlled tipping
hence, equation was amended by dropping C0 and adding ASCS and ASCI

11. Results and discussion (2)
all of the non-marketed choice attributes except LAND were highly significant and displayed the expected positive signs
the log-likelihood statistic for the initial data was higher than that of the extended procedure
the signs and significance of the coefficients from the new estimates offer more intuitive interpretations relative to the initial data
in addition, the Likelihood Ratio (LR) test also provides support that the extended procedure represents an improvement over the initial model.

12. Results and discussion (3)
the coefficients for ASCI and ASCS which are substantially higher relative to ASCC. The sign for ASCI is also negative as expected whereas ASCS is positive. This gives a hint that respondents may prefer sanitary landfill over incinerator
it also suggests that respondents may favour the status quo (controlled tipping) over incineration
however, both coefficients are insignificant even at the 10% level
additionally, statistical tests (LR) indicate that the null hypothesis that both ASCS and ASCI are equal to zero cannot be rejected.

13. Results and discussion (4)
insignificance of both ASCI and ASCS in the extended model may suggest that other heterogeneity existed, which the aggregate label ASCC was capturing in the initial data, and had little to do with the effect of specific technology labels
hence, it indicates that respondents in general have not been able to differentiate which of the two is more preferred.
this extended analysis has shown that there is no evidence that either disposal technology was preferred by respondents to replace the current option, i.e., controlled tipping

14. Results and discussion (5)
it implies that the labelled choice sets in the choice experiment analysis did not matter to respondents
respondents, as a whole, were only showing preferences over the attributes or the outcomes of the improved options, regardless of the specific technology

15. Conclusion
the results of this study do not lend support to a significant choice of specific waste disposal technology in the choice experiment analysis
the attributes or outcomes for each alternative technology remain the most important determinant of choice
the findings imply that the choice of SWD is not a mere normative debate about which technology is more socially acceptable, as widely presumed
what matters is whether any disposal plan would lead to obvious social benefits in terms of the major attributes
– air and river pollution impacts, and psychological
anxieties.

16. Conclusion (3)
requires the authorities to provide credible technical information while engaging the public rigorously to avoid any mistrust and misunderstandings
local authorities will be challenged to identify SWD sites that are technically and environmentally appropriate while socially desirable
early public consultation plan will be crucial in a society which is increasingly aware of the environment and their democratic rights
decision made without public involvement and later took defensive measures against public resentments may not be feasible in the future

17. Thank-you chuen.pek@nottingham.edu.my