\usepackage{xspace} \renewcommand{\vec}[1]{\mathbf{\boldsymbol{#1}}} \newcommand{\mat}[1]{\mathbf{#1}} %\newcommand{\diag}{\mathrm{diag}} %\newcommand{\trace}{\mathrm{trace}} \newcommand\equationname{Eq.} \newcommand\eg{\textit{e.g.},\xspace} \newcommand\ie{\textit{i.e.},\xspace} \newcommand\cf{\textit{cf.}\xspace} \newcommand{\pderiv}[2]{\frac{\partial #1}{\partial #2}} \newcommand{\pderivk}[3]{\frac{\partial^{#3} #1}{\partial #2^{#3}}} \newcommand{\deriv}[2]{\frac{\operatorname{d} #1}{\operatorname{d} #2}} \newcommand{\derivk}[3]{\frac{\operatorname{d}^{#3} #1}{\operatorname{d} #2^{#3}}} \newcommand{\integral}[4]{\int_{#3}^{#4} #1 \operatorname{d}#2} %\newcommand{\argmax}{\operatorname{argmax}} %\newcommand{\argmin}{\operatorname{argmin}} %\newcommand{\sign}{\operatorname{sign}} \newcommand{\smalleq}{{\scriptstyle =}} \newcommand{\quotes}[1]{``#1''} \newcommand\landau{\mathcal{O}} \newcommand\CONDON{\,|\,} \newcommand{\vectornorm}[1]{\left|\left|#1\right|\right|} \newcommand\kernelFunctionHIK{\kernelFunction^{\text{\scriptsize HIK}}} \newcommand\kernelFunctionGHIK{\kernelFunction^{\text{\scriptsize GHIK}}} \newcommand\mattwo[4]{\left[\begin{array}{cc} #1 & #2\\ #3 & #4 \end{array} \right]} \newcommand\matthree[9]{\left[\begin{array}{ccc} #1 & #2 & #3\\ #4 & #5 & #6\\ #7 & #8 & #9 \end{array} \right]} \newcommand\vectwo[2]{\left[\begin{array}{c} #1 \\ #2 \end{array} \right]} \newcommand\vecthree[3]{\left[\begin{array}{c} #1 \\ #2 \\ #3 \end{array} \right]} % notations \DeclareMathOperator{\x}{\boldsymbol{x}} \DeclareMathOperator{\y}{\boldsymbol{y}} \newcommand\labelspace{\mathcal{Y}} \newcommand\inputspace{\mathcal{X}} \newcommand\inputsingle{\vec{x}} \newcommand\inputsinglecomp{x} \newcommand\labelsingle{y} \newcommand\labelspecific{k} \newcommand\labelrandom{\labelsingle} \newcommand\inputrandom{\inputsingle} \newcommand\dataset{\mathcal{D}} \newcommand\dimension{D} \newcommand\noe{n} \newcommand\numberOfExamples{\noe} \newcommand\inputnew{\inputsingle^*} \newcommand\labelnew{\labelsingle_*} \newcommand\inputmatrix{\mat{X}} \newcommand\expectation{\mathbb{E}} \newcommand\cfunction{\tilde{h}} \newcommand\cestimate{\hat{h}} \newcommand\impuls[1]{\delta\left[#1\right]} \usepackage{upgreek} \newcommand\impulsDiscrete[1]{\updelta \left( {#1} \right)} \newcommand\numberOfClasses{M} \newcommand\error{\mbox{\textit{err}}} % model selection \newcommand\cparameters{\vec{\theta}} \newcommand\parameterspace{\Theta} \newcommand\labelvector{\vec{y}} \newcommand\inputdataset{\mat{X}} % kernel stuff \newcommand\meanFunction{\mu} \newcommand\kernelFunction{K} \newcommand\kernelMatrix{\mat{K}} \newcommand\kernelMatrixValue{K} \newcommand\kernelVector{\vec{k}_{*}} %\newcommand\kernelVector{\kernelFunction(\inputdataset, \inputnew)} \newcommand\kernelSelf{\kernelFunction(\inputnew, \inputnew)} % latent functions \newcommand\latentFunction{f} \newcommand\latentvector{\vec{f}} \newcommand\latentfunctionvalue{f} \newcommand\latentnew{f_*} \newcommand\ftransform{\phi} \newcommand\distance{d} \newcommand\rbfparameter{\gamma} \newcommand\featureSpace{\mathcal{H}} \newcommand\gpsymbol{\mathcal{GP}} \newcommand\meanfunction{\mathcal{M}} % model and modelspace / hypothesis, hypothesispace \newcommand\hypothesis{h} \newcommand\hypothesisSpace{\mathbb{H}} \newcommand\mapestimate[1]{ {\hat{#1}}^{\text{MAP}} } \newcommand\mlestimate[1]{ {\hat{#1}}^{\text{ML}} } \newcommand\bayesestimate[1]{ {\hat{#1}}^{\text{Bayes}} } \newcommand\mmseestimate[1]{ {\hat{#1}}^{\text{MMSE}} } \newcommand\mss[1]{\mbox{\scriptsize #1}} \newcommand\baggingFraction{r_{\mss{B}}} \newcommand\assumeeq{\stackrel{*}{=}} \newcommand\assumepropto{\stackrel{*}{\propto}} \newcommand\ensembleSize{T} \newcommand\ensembleIndex{t} \newcommand\dtthreshold{\zeta} \newcommand\thresholdSet{Q} \newcommand\featureindex{r} \newcommand\rFeatureSet{\mathcal{R}} \newcommand\leafNode{\vartheta} \newcommand\numberOfLeaves{m_\ell} \newcommand\node{v} \newcommand\splitCriterion{\Gamma} \newcommand\impurityMeasure{\mathcal{J}} \newcommand\entropy{\mathcal{E}} \newcommand\impurityThreshold{\xi_\impurityMeasure} \newcommand\minexamplesThreshold{\xi_{\mss{n}}} \newcommand\maxdepthThreshold{\xi_{\mss{d}}} \newcommand\hyperplane{\vec{w}} %\newcommand\stepFunction[1]{\delta^s\left[ #1 \right]} \newcommand\stepFunction[1]{\mbox{sign}\left(#1\right)} \newcommand\numberOfKernels{R} \newcommand\bias{b} \newcommand\margin{\mbox{mg}} \DeclareMathOperator\maximize{\mbox{maximize}} \DeclareMathOperator\minimize{\mbox{minimize}} \newcommand\hingeLoss{H} \newcommand\lagrangeDual{g} \newcommand\hyperparameters{\vec{\eta}} \newcommand\hyperparameter{\eta} \newcommand\kernelweight{\beta} \newcommand\kernelweights{\vec{\beta}} \newcommand\variance{\sigma^2} \newcommand\stddev{\sigma} \newcommand\eigmax{\lambda_{\text{max}}} \newcommand\eigmin{\lambda_{\text{min}}} % GP related stuff \newcommand\gpregmean{\mu_*} \newcommand\gpregvariance{\sigma^2_*} \newcommand\gpregstddev{\sigma_*} % differential symbol for integrals \newcommand\diffd{d} \newcommand\kernelscaling{v_0} \newcommand\kernelbias{v_1} \newcommand\qexpgrad{g} %\newcommand\gpnoise{\sigma_{\varepsilon}^2} \newcommand\gpnoise{\sigma^2} \newcommand\gpnoisestddev{\sigma_{\varepsilon}} %\newcommand\identityMatrix[1]{\mat{I}_{(#1)}} \newcommand\identityMatrix[1]{\mat{I}} \newcommand\kernelStuff{\zeta_\kernelFunction} % gp classification \newcommand\cumgauss{\Phi} \newcommand\cumgaussLoss{L_{\cumgauss}} \DeclareMathOperator\sigmoid{\mbox{sig}} \newcommand\sigmoidLoss{L_{\scriptsize \text{sig}}} \DeclareMathOperator\erf{\mbox{erf}} % gp classification scaling factor \newcommand\gpnoiseC{\sigma_{c}^2} \newcommand\gpnoisestddevC{\sigma_{c}} % laplace methods \newcommand\laplaceMode{\vec{\hat{f}}} \newcommand\laplaceModeValue{\hat{f}} \newcommand\laplaceLog{L} \newcommand\approxP{q} \newcommand\constTerm{\text{\textit{const.}}} \newcommand\nhessianLikelihood{\mat{W}} \newcommand\nhessianLikelihoodValue{W} % gp multi \newcommand\ymulti{y_*^{\scriptsize \mbox{multi}}} \newcommand\ymultip{y_*^{\scriptsize \mbox{multi}}} % gp hyperparameter estimation \newcommand\kernelMatrixHyper{\mat{\tilde{K}}_\hyperparameters} % optimization problems \newcommand\optimizationProblem[5]{ \begin{equation} \label{#1} \begin{aligned} & \underset{#3}{#2} & & #4 \\ & \text{subject to} & & #5 \enspace. \end{aligned} \end{equation} } \newcommand\optimizationProblemUnconstrained[4]{ \begin{equation} \label{#1} \begin{aligned} & \underset{#3}{#2} & & #4 \enspace.\\ \end{aligned} \end{equation} } % transfer learning framework %\newcommand\targetTask{\mathcal{T}} \newcommand\targetTask{\tau} \newcommand\supportTag{\mathcal{S}} \newcommand\datasetSupport[1]{{\dataset}^{\supportTag}_{#1}} \newcommand\datasetSupportSingle{{\dataset}^{\supportTask}} \newcommand\datasetTarget{{\dataset}^{\targetTask}} \newcommand\supportCollection{\mathfrak{D}^{\supportTag}} \newcommand\numberOfTasks{J} \newcommand\numberOfTasksMT{P} \newcommand\noeTarget{\tilde{\noe}} \newcommand\noeTotal{\noe} \newcommand\noePositive{\noe_1} \newcommand\noeSupport{\noe^{\supportTag}} \newcommand\supportClasses{\supportTag} \newcommand\supportClass{s} \newcommand\backgroundClass{\mathcal{B}} \newcommand\transferParameter{\vec{\theta}} \newcommand\tpSpace{\Theta} % regularized trees \newcommand\targetClass{\targetTask} \newcommand\rtPara{\vec{\theta}} \newcommand\rtParaValue{\theta} \newcommand\rtHyperMu{\vec{\mu}} \newcommand\rtHyperMuValue{\mu} %\newcommand\rtHyperSigma{\sigma_{\supportTag}} \newcommand\rtHyperVariance{\sigma^2} \newcommand\leafIndex{i} \newcommand\datasetLeaf[1]{\omega_{#1}} %\newcommand\datasetLeaf[1]{\dataset^{\ell}_{#1}} %\newcommand\rtLeafProbs[1]{\vec{t}_{\supportTag}^{#1}} \newcommand\rtLeafProbs[1]{\vec{t}^{(#1)}} \newcommand\rtLeafProb[2]{t^{(#1)}_{#2}} \newcommand\lagrange{L} %\newcommand\mcdata[1]{\dataset^{#1}} \newcommand\mcdata[1]{\dataset^{#1}} %\newcommand\rtML[2]{\hat{\theta}^{\mss{(ML)},#2}_{#1}} \newcommand\rtML[2]{t^{(#1)}_{#2}} \newcommand\rtMLv[1]{\vec{t}^{(#1)}} \newcommand\rtParaSpace{\Theta} % only for the target task \newcommand\rtMAPv{\vec{\hat{\theta}}^{\mss{MAP}}} \newcommand\leafCounts{\vec{c}} \newcommand\leafCount{c} \newcommand\leafNodeBinaryV{\ftransform} \newcommand\rtPostProbsV[1]{w^{\left(#1\right)}} \newcommand\leafNodeBinary{\ftransform} \newcommand\rtPostProbs[1]{\vec{w}^{\left(#1\right)}} % feature relevance \newcommand\featureSet{\mathcal{F}} \newcommand\featureFunction{g} \newcommand\frPara{\vec{\theta}} \newcommand\frParaValue{\theta} \newcommand\frBaseModel{h} \newcommand\frBaseModelSpace{H} \newcommand\frHyper{\vec{\beta}} \newcommand\frHyperValue{\beta} %\newcommand\ % depgp \newcommand\depgpcorr{\rho} \newcommand\tT{\textcolor{green}{\targetTask}} \newcommand\tS{\textcolor{blue}{\supportTask}} %\newcommand\supportTask{\supportTag} \newcommand\supportTask{s} \newcommand\depgpKNoColor{ \left(\begin{array}{cc} \kernelMatrix_{\targetTask \targetTask} & \depgpcorr \kernelMatrix_{\targetTask \supportTask}\\ \depgpcorr \kernelMatrix_{\targetTask \supportTask}^T & \kernelMatrix_{\supportTask \supportTask}\end{array}\right) } \newcommand\depgpK{ \LARGE\left(\begin{array}{cc} \kernelMatrix_{\tT \tT} & \depgpcorr \kernelMatrix_{\tT \tS}\\ \depgpcorr \kernelMatrix_{\tT \tS}^T & \kernelMatrix_{\tS \tS}\end{array}\right) } \newcommand\depgpKNoColorInd{ \left(\begin{array}{cc} \kernelMatrix_{\targetTask \targetTask} & \mat{0}\\ \mat{0} & \kernelMatrix_{\supportTask \supportTask}\end{array}\right) } \newcommand\kernelFunctionX{\kernelFunction^{\inputspace}} \newcommand\kernelMatrixX{\kernelMatrix^{\inputspace}} \newcommand\kron{\otimes} \newcommand\taskIndex{j} \newcommand\kernelVectorTarget{\vec{k}_{\targetTask*}} \newcommand\kernelVectorSupport{\vec{k}_{\supportTask*}} \newcommand\labelvectorTarget{\labelvector_{\targetTask}} \newcommand\labelvectorSupport{\labelvector_{\supportTask}} \newcommand\inputdatasetTarget{\inputdataset_{\targetTask}} \newcommand\inputdatasetSupport{\inputdataset_{\supportTask}} \newcommand\loovariance{\tilde{\sigma}^2} \newcommand\loomean{\tilde{\mu}} \newcommand\kF{\mat{K}^{\latentfunction}} \newcommand\kFTasks[2]{K^{\latentfunction}_{#1 #2}} \newcommand\latentfunctionS{\tilde{\latentfunction}} \newcommand\kernelFunctionS{\tilde{\kernelFunction}} \newcommand\latentfunctionB{\bar{\latentfunction}} \newcommand\kernelFunctionB{\bar{\kernelFunction}} \newcommand\pilonettoWeight{\alpha} \newcommand\wnsim{d} % ------ tommasi \newcommand\tommasiBeta{\beta} \newcommand\hyperplaneTarget{\hyperplane^{(\targetTask)}} \newcommand\hyperplaneSupport{\hyperplane^{(\supportTask)}} \newcommand\alphaSupport{\vec{\alpha}^{(\supportTask)}} \newcommand\alphaTarget{\vec{\alpha}^{(\targetTask)}} \newcommand\alphaTargetValue{\alpha^{(\targetTask)}} % ------ occ \newcommand\occScore{\nu} \newcommand\occThreshold{\xi} \newcommand\ftMatrix{\mat{\Phi}} \newcommand\kernelMatrixReg{\kernelMatrix_{\mss{reg}}} \newcommand\covarianceReg{\mat{C}_{\mss{reg}}} \newcommand\covarianceMatrix{\mat{C}} \newcommand\ftmean{\vec{\mu}_{\ftMatrix}} \newcommand\ftransformC{\tilde{\ftransform}} \newcommand\squashFunction{\Phi} \newcommand\radiusBall{R} \newcommand\meanBall{\vec{m}} % ------- local features \newcommand\dimensionLF{S} \newcommand\localfeature{\vec{l}} \newcommand\lfposition{\vec{p}} \newcommand\numberOfLFeat{W} \newcommand\lfSet{\mathcal{L}} % -------------- comparing histograms \newcommand\setA{\mathcal{A}} \newcommand\setB{\mathcal{B}} \newcommand\baseSet{\mathcal{U}} \newcommand\powerSet[1]{\mathcal{P}\left(#1\right)} \newcommand\distSet{d} \newcommand\clusterq{q} \newcommand\numberOfClusters{n_q} % -------------- BoF \newcommand\bofHist{\vec{h}} \newcommand\bofHistValue{h} \newcommand\bofIndex{j} % -------------- SIFT \newcommand\aimg{\mathfrak{g}} \newcommand\apoint{\vec{p}} \newcommand\gaussianFilter[1]{\mathfrak{h}_{#1}} \newcommand\gaussianScale{\sigma} \newcommand\illuminationFunction{u} \newcommand\greyValue{g} \newcommand\conv{*} % --------- pyramid matching \newcommand\matchingError{\error_{\pi}} \newcommand\pmkLevel{\ell} \newcommand\numPMKLevels{L} \newcommand\pmkHist{\vec{h}} \newcommand\pmkHistValue{h} \newcommand\pmkData{\mat{H}} \newcommand\pmkSimilarity{\kernelFunction^{\mss{PMK}}} \newcommand\pmkSimilarityNormalized{\tilde{\kernelFunction}^{\mss{PMK}}} \newcommand\pmkMatches{I} % --------- experiments \newcommand\numRuns{Z} \newcommand\confusionMatrix{\mat{C}} \newcommand\confusionMatrixValue{C} \newcommand\noeTest{\noe^{\mss{t}}} %\newcommand\recogRate{\error^{\mss{ov}}} %\newcommand\avgRecogRate{\error^{\mss{avg}}} \newcommand\recogRate{\text{err-ov}} \newcommand\avgRecogRate{\text{err-avg}} \newcommand\ctp{\text{TP}} \newcommand\cfp{\text{FP}} \newcommand\cfn{\text{FN}} \newcommand\ctn{\text{TN}} \newcommand\numPositives{\noe_{\mss{pos}}} \newcommand\numNegatives{\noe_{\mss{neg}}} \newcommand\tprate{\text{TPR}} \newcommand\fprate{\text{FPR}}