## 2 Harmony Search Algorithm and Selected Variants
### Improved Harmony Search (IHS)
** The burdensome process of finding an appropriate range of the parameters for each data set are evaded by using the complete range of the parameters, regardless of the data set. This may increase the computational time, but it can be traded off with better computing resources. 3. **No in-depth information about the infectious disease is necessary. ** HS optimization can well be applied to other infectious disease modeling without extra specific information about the disease. ## 5 Conclusions and Future Work

The application of HS is a novel approach in the field of epidemiology, particularly in epidemiological modeling. In this study, HS was implemented in order to estimate the epidemiological parameters of the prototypical compartmental SIR model as an optimization problem. Ten variants of HS algorithm were applied on five data sets to simulate the trajectory of COVID-19 cumulative infectious cases. The computational experiments demonstrated the ability of HS to be successfully applied to epidemiological modeling and as an efficacious estimator for the model parameters. As such, HS is proposed as a potential alternative estimation tool for the epidemiological parameters. An interesting insight from this study is that SHS is competent enough and it exhibited comparable performance with the rest of the HS variants in this particular application of HS optimization. For future work, the application of HS can be expanded to parameter estimations in advanced compartmental epidemiological models (e.g.,: SEIR model) and to the modeling of other existing infectious diseases (e.g.,: H1N1) or potential novel infectious diseases in the future. Conceptualization, K.G. and L.S.L. ; methodology, K.G. and L.S.L. ; software, K.G. ; validation, K.G., L.S.L. and H.-V.S. ; formal analysis, K.G., L.S.L. and H.-V.S. ; investigation, K.G. and L.S.L. ; writing--original draft preparation, K.G. and L.S.L. ; writing--



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