id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-175366-jomeywqr	Massonis, Gemma	Structural Identifiability and Observability of Compartmental Models of the COVID-19 Pandemic	2020-06-25		.txt	text/plain	6470	386	45	We analyse the structural identifiability and observability of all of the models, considering all plausible choices of outputs and time-varying parameters, which leads us to analyse 255 different model versions. It should be taken into account that in the present work we are interested in assessing structural identifiability and observability both with constant and continuous time-varying model parameters (or equivalently, with unknown inputs), as explained in Remark 1. The recovered state (R) is almost never observable unless it is directly measured (D.M.) as output; the only exceptions are two SEIR models, 31 and 38, for which R is observable under the assumption of time-varying parameters. Changing β from a constant to a time-varying parameter (or equivalently an unknown input) does not change its observability nor that of the other variables in SIR models. Considering the recovery rate γ (Fig. 7) or the latent period κ (Fig. 6) individually as time-varying parameters generally leads to greater observability, except for model 31 (1) .	./cache/cord-175366-jomeywqr.txt	./txt/cord-175366-jomeywqr.txt