ML之回归预测之Lasso:利用Lasso算法解决回归(实数值评分预测)问题—优化模型【增加新(组合)属性】
目录
输出结果
设计思路
核心代码
输出结果
设计思路
核心代码
names[-1] = "a^2"
names.append("a*b")
nrows = len(xList)
ncols = len(xList[0])
xMeans = []
xSD = []
for i in range(ncols):
col = [xList[j][i] for j in range(nrows)]
mean = sum(col)/nrows
xMeans.append(mean)
colDiff = [(xList[j][i] - mean) for j in range(nrows)]
sumSq = sum([colDiff[i] * colDiff[i] for i in range(nrows)])
stdDev = sqrt(sumSq/nrows)
xSD.append(stdDev)
X = numpy.array(xList) #Unnormalized X's
X = numpy.array(xNormalized) #Normlized Xss
Y = numpy.array(labels) #Unnormalized labels