【机器学习笔记】Machine Learning Fundamentals: Bias(偏差)、Variance(方差)、Overfit(过度拟合)

图像常见噪声介绍 图像常见的四种噪声:高斯噪声,泊松噪声,乘性噪声,椒盐噪声。  高斯噪声是指它的概率密度函数服从高斯分布(即正态分布)的一类噪声。常见的高斯噪声包括起伏噪声、宇宙噪声、热噪声和散粒噪声等等。除常用抑制噪声的方法外,对高斯噪声的抑制方法常常采用数理统计方法。 泊松噪声是符合泊松分布的噪声模型,泊松分布适合于描述单位时间内随机事件发生的次数的概率分布。如某一服务设施在一定时间内受到的服务请求的 阅读详情

假设有一群老鼠,我们测量,并在二维坐标系中记录它们的身高以及对应的体重,这些点似乎都在某一条曲线的附近,但我们并不知道准确的方程式,所以我们可以使用两种机器学习的方法来估算它们的关系(直线和波纹线)。

我们要做的第一件事情是将数据划分成两个部分,一部分用作训练机械学习的算法,另一部分用作测试。

我们要使用的第一种机器学习算法是线性回归(Linear Regression),也称作“最小二乘法”。

但无论我们怎样调整直线的角度,由于直线不能包含弧度,线性回归直线永远捕获不了 Height 与 Weight 的真正关系。

这种无法捕获的情况称为偏差(Bias)。

【重磅干货整理】机器学习(Machine Learning)与深度学习(Deep Learning)资料汇总-附件资源 立即下载

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