Symbols and Abbreviations

The main symbols and abbreviations used throughout the text are listed as follows.

    absolute value of a real number

    Euclidean norm of a vector

    inner product

    indicator function

    expectation value of a random variable

    first-order derivative of the function

    second-order derivative of the function

    gradient of the function with respect to

    sign function

    Gamma function

    vector or matrix transposition

    identity matrix

    inverse of matrix

    determinant of matrix

    trace of matrix

    rank of matrix

    natural logarithm function

    unit delay operator

    real number space

    -dimensional real Euclidean space

    correlation coefficient between random variables and

    variance of random variable

    probability of event

    Gaussian distribution with mean vector and covariance matrix

    uniform distribution over interval

    chi-squared distribution with degree of freedom

    Shannon entropy of random variable

    -entropy of random variable

    -order Renyi entropy of random variable

    -order information potential of random variable

    survival information potential of random variable

    -entropy of discrete random variable

    mutual information between random variables and

    KL-divergence between random variables and

    -divergence between random variables and

    Fisher information matrix

    Fisher information rate matrix

    probability density function

    Mercer kernel function

    kernel function for density estimation

    kernel function with width

    Gaussian kernel function with width

    reproducing kernel Hilbert space induced by Mercer kernel

    feature space induced by Mercer kernel

    weight vector

    weight vector in feature space

    weight error vector

    step size

    sliding data length

MSE    mean square error

LMS    least mean square

NLMS    normalized least mean square

LS    least squares

RLS    recursive least squares

MLE    maximum likelihood estimation

EM    expectation-maximization

FLOM    fractional lower order moment

LMP    least mean -power

LAD    least absolute deviation

LMF    least mean fourth

FIR    finite impulse response

IIR    infinite impulse response

AR    auto regressive

ADALINE    adaptive linear neuron

MLP    multilayer perceptron

RKHS    reproducing kernel Hilbert space

KAF    kernel adaptive filtering

KLMS    kernel least mean square

KAPA    kernel affine projection algorithm

KMEE    kernel minimum error entropy

KMC    kernel maximum correntropy

PDF    probability density function

KDE    kernel density estimation

GGD    generalized Gaussian density

    symmetric -stable

MEP    maximum entropy principle

DPI    data processing inequality

EPI    entropy power inequality

MEE    minimum error entropy

MCC    maximum correntropy criterion

IP    information potential

QIP    quadratic information potential

CRE    cumulative residual entropy

SIP    survival information potential

QSIP    survival quadratic information potential

KLID    Kullback–Leibler information divergence

EDC    Euclidean distance criterion

MinMI    minimum mutual information

MaxMI    maximum mutual information

AIC    Akaike’s information criterion

BIC    Bayesian information criterion

MDL    minimum description length

FIM    Fisher information matrix

FIRM    Fisher information rate matrix

MIH    minimum identifiable horizon

ITL    information theoretic learning

BIG    batch information gradient

FRIG    forgetting recursive information gradient

SIG    stochastic information gradient

SIDG    stochastic information divergence gradient

SMIG    stochastic mutual information gradient

FP    fixed point

FP-MEE    fixed-point minimum error entropy

RFP-MEE    recursive fixed-point minimum error entropy

EDA    estimation of distribution algorithm

SNR    signal to noise ratio

WEP    weight error power

EMSE    excess mean square error

IEP    intrinsic error power

ICA    independent component analysis

BSS    blind source separation

CRLB    Cramer–Rao lower bound

AEC    acoustic echo canceller