Gradient Descent Ascent in Min-Max Stackelberg GamesDenizalp GoktasBrown UniversityComputer ScienceProvidence, Rhode Island, USAdenizalp_goktas@brown.eduAmy GreenwaldBrown UniversityComputer ScienceProvidence, Rhode Island, USAamy_greenwald@brown.eduABSTRACTMin-max optimization problems (i.e., min-max games...
在这里明确了梯度下降是“找到使函数值最小的那个自变量X”,换句话说,在常见的的分类问题中,就算找到使损失函数(Loss Function)最小的那个参数 θ 。这是梯度下降,找到全局最小值(当然大概率是局部最小值) 在强化学习中,我们没有确切的损失函数,我们无法让损失最小,代替的目标是最大化奖励函数(Reward Function)...
Gradient descentis afirst-orderiterativeoptimizationalgorithmfor finding alocal minimumof a differentiable function. To find a local minimum of a function using gradient descent, we take steps proportional to thenegativeof thegradient(or approximate gradient) of the function at the current point. But ...
One of the most popular algorithms for solving this problem is the celebrated gradient descent ascent (GDA) algorithm, which has been widely used in machine learning, control theory and economics. Despite the extensive convergence results for the convex-concave setting, GDA with equal stepsize can...
Gradient ascent works in the same manner as gradient descent, with one difference. The task it fulfills isn’t minimization, but rather maximization of some function. The reason for the difference is that, at times, we may want to reach the maximum, not the minimum of some function; this...
GAN中gradient descent-ascent,收敛性(尤其wT的)无法得以保证,也暗示它需要更复杂的优化算法。 如果有strong convexity(要求了下界的梯度增量;convexity不限定梯度,可以0,可以无穷小),可以得到last iterate的optimality gap,在逐渐趋近于0【TODO: strong convexity和convexity的差距以及该差距对上述理论分析带来的影响】 学...
2. Directional Derivative 3. Gradient Descent (opposite = Ascent) https://www.khanacademy.org/math/multivariable-calculus/multivariable-derivatives/gradient-and-directional-derivatives/v/why-the-gradient-is-the-direction-of-steepest-ascent Deeplearning with Gradient Descent: AIGradient Descent Why...
Mini-Batches and Stochastic Gradient Descent (SGD) Learning Rate Scheduling Maximizing Reward with Gradient Ascent Q&A: 5 minutes Break: 10 minutes Segment 3: Fancy Deep Learning Optimizers (60 min) A Layer of Artificial Neurons in PyTorch Jacobian Matrices Hessian Matrices and Second-Order Op...
1.梯度下降法(Gradientdescent) 梯度下降法,通常也叫最速下降法(steepestdescent),基于这样一个事实:如果实值函 数f(x)在点x处可微且有定义,那么函数f(x)在x点沿着负梯度(梯度的反方向)下降最快。 假设x是一个向量,考虑f(x)的泰勒展开式: )( ,)()())(()()()( 1 2 是方向向量为步长标量;其中 ...
Stochastic Recursive Gradient Descent Ascent for Stochastic Nonconvex-Strongly-Concave Minimax Problems We consider nonconvex-concave minimax optimization problems of the form minxmaxy∈Yf(x,y), where f is strongly-concave in y but possibly nonconvex in x and Y is a convex and compact set. We ...