h.amise {kedd} | R Documentation |
AMISE for Optimal Bandwidth Selectors
Description
The (S3) generic function h.amise
evaluates the asymptotic
mean integrated squared error AMISE for optimal smoothing
parameters h
of r'th derivative of kernel density
estimator one-dimensional.
Usage
h.amise(x, ...)
## Default S3 method:
h.amise(x, deriv.order = 0, lower = 0.1 * hos, upper = 2 * hos,
tol = 0.1 * lower, kernel = c("gaussian", "epanechnikov", "triweight",
"tricube", "biweight", "cosine"), ...)
Arguments
x |
vector of data values. |
deriv.order |
derivative order (scalar). |
lower , upper |
range over which to minimize. The default is
almost always satisfactory. |
tol |
the convergence tolerance for |
kernel |
a character string giving the smoothing kernel to be used, with default
|
... |
further arguments for (non-default) methods. |
Details
h.amise
asymptotic mean integrated squared error implements for choosing
the optimal bandwidth h
of a r'th derivative kernel density estimator.
We Consider the following AMISE version of the r'th derivative of f
the r'th
derivative of the kernel estimate (see Scott 1992, pp 131):
AMISE(h;r)= \frac{R\left(K^{(r)}\right)}{nh^{2r+1}} + \frac{1}{4} h^{4} \mu_{2}^{2}(K) R\left(f^{(r+2)}\right)
The optimal bandwidth minimizing this function is:
h_{(r)}^{\ast} = \left[\frac{(2r+1)R\left(K^{(r)}\right)}{\mu_{2}^{2}(K) R\left(f^{(r+2)}\right)}\right]^{1/(2r+5)} n^{-1/(2r+5)}
whereof
\inf_{h > 0} AMISE(h;r) = \frac{2r+5}{4} R\left(K^{(r)}\right)^{\frac{4}{(2r+5)}} \left[ \frac{\mu_{2}^{2}(K)R\left(f^{(r+2)}\right)}{2r+1} \right]^{\frac{2r+1}{2r+5}} n^{-\frac{4}{2r+5}}
which is the smallest possible AMISE for estimation of f^{(r)}(x)
using the kernel K(x)
,
where R\left(K^{(r)}\right) = \int_{R} K^{(r)}(x)^{2} dx
and \mu_{2}(K) = \int_{R}x^{2} K(x) dx
.
The range over which to minimize is hos
Oversmoothing bandwidth, the default is almost always
satisfactory. See George and Scott (1985), George (1990), Scott (1992, pp 165), Wand and Jones (1995, pp 61).
Value
x |
data points - same as input. |
data.name |
the deparsed name of the |
n |
the sample size after elimination of missing values. |
kernel |
name of kernel to use |
deriv.order |
the derivative order to use. |
h |
value of bandwidth parameter. |
amise |
the AMISE value. |
Author(s)
Arsalane Chouaib Guidoum acguidoum@usthb.dz
References
Bowman, A. W. and Azzalini, A. (1997). Applied Smoothing Techniques for Data Analysis: the Kernel Approach with S-Plus Illustrations. Oxford University Press, Oxford.
Radhey, S. S. (1987). MISE of kernel estimates of a density and its derivatives. Statistics and Probability Letters, 5, 153–159.
Scott, D. W. (1992). Multivariate Density Estimation. Theory, Practice and Visualization. New York: Wiley.
Sheather, S. J. (2004). Density estimation. Statistical Science, 19, 588–597.
Silverman, B. W. (1986). Density Estimation for Statistics and Data Analysis. Chapman & Hall/CRC. London.
Wand, M. P. and Jones, M. C. (1995). Kernel Smoothing. Chapman and Hall, London.
See Also
plot.h.amise
, see nmise
in package sm this function
evaluates the mean integrated squared error of a density estimate (deriv.order = 0
)
which is constructed from data which follow a normal distribution.
Examples
## Derivative order = 0
h.amise(kurtotic,deriv.order = 0)
## Derivative order = 1
h.amise(kurtotic,deriv.order = 1)