如果将所有的Θ初始化为0会怎样？
如果
[Theta _{ij}^{left( l ight)} = 0]
那么
[egin{array}{l}
a_1^{left( 2
ight)} = a_2^{left( 2
ight)}\
delta _1^{left( 2
ight)} = delta _2^{left( 2
ight)}\
frac{partial }{{partial Theta _{01}^{left( 1
ight)}}}Jleft( Theta
ight) = frac{partial }{{partial Theta _{02}^{left( 1
ight)}}}Jleft( Theta
ight)\
...
end{array}]
这就导致
After each update, parameters corresponding to inputs going into each of two hidden units are identical
在每次更新之后，对应于进入两个隐藏单元中的每一个的输入的参数是相同的
解决方法是随机生成参数值