TY - JOUR
T1 - Free ticket, discount ticket or intermediate of the best of two worlds – Which subsidy policy is socially optimal to suppress the disease spreading?
AU - Tatsukawa, Yuichi
AU - Arefin, Md Rajib
AU - Tanaka, Masaki
AU - Tanimoto, Jun
N1 - Funding Information:
This study was partially supported by Grant-in-Aid for Scientific Research from JSPS, Japan, KAKENHI (Grant No. JP 19KK0262 , JP 20H02314A , and JP 20K21062 ) awarded to Professor Tanimoto. We would like to express our gratitude to them.
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/7/7
Y1 - 2021/7/7
N2 - With the aid of the evolutionary vaccination game on a scale-free network, we design a new subsidy policy, named degree dependent subsidy, where cooperative agents get incentives according to their connectivity or degree. That is, agents, having a greater degree, receive a higher incentive, and vice versa. Here we presume that vaccinators are cooperative agents. The new scheme can be said to an intermediate policy between two previously studies policies, namely free ticket and flat discount policies. The former policy distributes free tickets to cooperative hub agents as a priority, whereas the latter dispenses a fixed discount to every cooperator. We compare the efficiency of each policy in terms of having a less infectious state with a minimum social cost. While investigating the performance of the three policies in terms of average social payoff–which takes into account the cost of vaccination as well as infection–the free ticket scheme is found to be the most appealing policies among the three when the budget for subsidy is quite low. The degree dependent subsidy policy outperforms others for a moderate budget size, while the flat discount policy requires a higher budget to effectively suppress the disease. We further estimate threshold levels of the subsidy budget for each policy beyond which subsidizing results in excessive use of vaccination. As a whole, concerning vaccination coverage and final epidemic size, the degree-dependent subsidy scheme outperforms the flat discount scheme, but is dominated by the free ticket policy.
AB - With the aid of the evolutionary vaccination game on a scale-free network, we design a new subsidy policy, named degree dependent subsidy, where cooperative agents get incentives according to their connectivity or degree. That is, agents, having a greater degree, receive a higher incentive, and vice versa. Here we presume that vaccinators are cooperative agents. The new scheme can be said to an intermediate policy between two previously studies policies, namely free ticket and flat discount policies. The former policy distributes free tickets to cooperative hub agents as a priority, whereas the latter dispenses a fixed discount to every cooperator. We compare the efficiency of each policy in terms of having a less infectious state with a minimum social cost. While investigating the performance of the three policies in terms of average social payoff–which takes into account the cost of vaccination as well as infection–the free ticket scheme is found to be the most appealing policies among the three when the budget for subsidy is quite low. The degree dependent subsidy policy outperforms others for a moderate budget size, while the flat discount policy requires a higher budget to effectively suppress the disease. We further estimate threshold levels of the subsidy budget for each policy beyond which subsidizing results in excessive use of vaccination. As a whole, concerning vaccination coverage and final epidemic size, the degree-dependent subsidy scheme outperforms the flat discount scheme, but is dominated by the free ticket policy.
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U2 - 10.1016/j.jtbi.2021.110682
DO - 10.1016/j.jtbi.2021.110682
M3 - Article
C2 - 33744309
AN - SCOPUS:85103328737
VL - 520
JO - Journal of Theoretical Biology
JF - Journal of Theoretical Biology
SN - 0022-5193
M1 - 110682
ER -