## Parameter estimation - How to input experiment data?

### Deepa Maheshvare (view profile)

on 7 Apr 2019
Latest activity Commented on by dpb

### dpb (view profile)

on 21 Apr 2019
Hi All,
I want to perform parameter estimation of the following ode model.
5 parameters have to be estimated after performing a least square error minimization of the cost function. The input that I have is steady state multi -experiment values of y1 to y10.
I found an example here that illustrated how to input time series experiment data. Could someone explain how to input staedy state multi-experiment data?

dpb

### dpb (view profile)

on 21 Apr 2019
The mat4bc function accepts the arguments ya,yb which is the shorthand nomenclature for the y of the ode function at [a,b] of the interval.
In the example (and for any SS solution), the BC for the derivative is zero which is what is yb(2) returns.
The example has three BCs so the function returns three values; if your case has additional, you simply set the other terms of ya,yb appropriately. However, you have to be certain the system is not over-constrained by more BCs than are DOF to match--iow, must be realizable.
Deepa Maheshvare

### Deepa Maheshvare (view profile)

on 21 Apr 2019
Thanks a lot for the response. In my case, there are 10 variables. Basically, the
arguments ya and yb are column vectors of 10 rows each.
I'm not sure if I follow this,
"you have to be certain the system is not over-constrained by more BCs than are DOF to match--iow, must be realizable".Could you please explain?
dpb

### dpb (view profile)

on 21 Apr 2019
Just like you couldn't fit a quadratic equation to only two points, you can't try to force more conditions onto the solution of your set of PDEs than can be achieved.
Just an observation on a elementary fact; it's sometimes not so easy to tell with such a system of equations what isn't feasible when setting constraints unless there is a closed-form solution that you can examine.