���������������������������������������������������������������������������������������
nounced when marketing is reduced but consumer experience is still negative . This occurs because the only counterbalance to the negative WOM is the existing positive views , which are diminished over time .
Analysis of the surface plot ( see Figure 9 ) suggests certain thresholds for market growth . In effect , the consumer view must be positive by the time marketing for platform introduction has ended to achieve the sharp increase in ethanol consumption . The strength of consumer experience is observed to be more dominant than marketing in determining ethanol demand and SO vehicle market share . When the experience is poor (< 0 ), marketing is unable to generate substantial increase in ethanol consumption , and when the experience is positive (> 0 ) there is diminishing return on marketing investment especially above $ 150 million / year .
Discussion
The results show the importance of
including unfavorable views and
WOM in the SO market model and understanding their mechanism of influence on the observed system behavior . Although all models can be considered wrong to some degree , they can inform policy development by providing valuable insight into the behavior and sensitivities of components of the system in question ( Sterman , 2002 ). This discussion focuses on the importance of including unfavorable perceptions , and multiple stakeholders and assumes the precision of the results is of secondary importance . The application of loop knockout illustrates the difference between the behavior seen in the existing single stakeholder model and new model . A key difference is the ability to allow for a change in reinforcing social exposure loops from a virtuous to a vicious cycle .
Fuel choice , and the ability of the market to maintain adequate supply and price point , plays a role in influencing the consumer perception and vehicle utility . Although the instantaneous perception and utility of the SO fuel can quickly change , the views of the vehicle owners are harder to change . This can lead to persistent negative reinforcement than can undermine long-term prospects for the technology platform , and place increased importance of accommodating all stakeholder needs in the earlier years of technology deployment .
The influence of unfavorable WOM depends on consumer satisfaction , rates of forgetting , and rates of conversion . If the rate of forgetting is very high , this reduces down to the immediate experience and the ratio of favorable to unfavorable WOM . The end result is a delay in market growth until adequate utility is reestablished and favorable WOM dominates the social diffusion . As long as some unfavorable views exist , the rate of market growth and carrying capacity will always be lower than what is observed in the Keith model and projected in current policy and regulations , and will either follow a reduced positive trajectory or stagnate . However , under more severe conditions unfavorable WOM will dominate after initial market introduction and can lead to a reverse tipping point in which the market collapses through the growth of the unfavorable view . In the case suggested by Chen , et al . ( 2013 ) and Denrell ( 2008 ) where consumer forgetting of unfavorable experiences is zero or very low and risk aversion to new technology remains high the stock of unfavorable views will continue to grow and erode the potential market capacity ( favorable view stock ) even when the consumer experience is very high and conversion of favorable views to purchase of SO capable vehicles is high . The total flow of new SO vehicle purchases will re-
126