optK: Function used in the EM algorithm to estimate kappa...
In MarieAugerMethe/CCRWvsLW: Searching strategy movement models
Description
Usage
Arguments
Details
Description
Even with the CDLL, the kappa value cannot found analytically. This function minimizes the part that needs to be minimized numerically.
Usage
1
optK(t2)
Arguments
t2
double: part of the derivative, see details
Details
The get maximum likelihood estimate for kappa using the CDLL, we need to solve the following equation: 0 = I_1(kappa)/I_0(kappa) - sum (E(u_j(t))*cos(x_t))/sum(E(u_j(t))), where I_1 and I_0 are the modified Bessel functions. This equation is hard to solve analytically and optK uses the function optimize to numerically minimize: abs((besselI(k, 1)/besselI(k,0)) - t2), where t2 is: sum (E(u_j(t))*cos(x_t))/sum(E(u_j(t))). This is only done for the extensive behavior (j=2). The kappa of the intensive behavior (j=1) is fixed to 0 (uniform distribution).
MarieAugerMethe/CCRWvsLW documentation built on May 7, 2019, 2:50 p.m.
R Package Documentation
Browse R Packages
We want your feedback!
Note that we can't provide technical support on individual packages. You should contact the package authors for that.
Description Usage Arguments Details
Description
Even with the CDLL, the kappa value cannot found analytically. This function minimizes the part that needs to be minimized numerically.
Usage
1 | optK(t2)
|
Arguments
t2 |
double: part of the derivative, see details |
Details
The get maximum likelihood estimate for kappa using the CDLL, we need to solve the following equation: 0 = I_1(kappa)/I_0(kappa) - sum (E(u_j(t))*cos(x_t))/sum(E(u_j(t))), where I_1 and I_0 are the modified Bessel functions. This equation is hard to solve analytically and optK uses the function optimize to numerically minimize: abs((besselI(k, 1)/besselI(k,0)) - t2), where t2 is: sum (E(u_j(t))*cos(x_t))/sum(E(u_j(t))). This is only done for the extensive behavior (j=2). The kappa of the intensive behavior (j=1) is fixed to 0 (uniform distribution).
R Package Documentation
Browse R Packages
We want your feedback!
Note that we can't provide technical support on individual packages. You should contact the package authors for that.
Embedding an R snippet on your website
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.