Double lr_mult params

[Fabio Maria Carlucci]

In many networks I see:

layer {
  name: "fc6"
  type: "InnerProduct"
  bottom: "pool5"
  top: "fc6"
  param {
    lr_mult: 1
    decay_mult: 1
  }
  param {
    lr_mult: 2
    decay_mult: 0
  }
  inner_product_param {
    num_output: 4096
    weight_filler {
      type: "gaussian"
      std: 0.005
    }
    bias_filler {
      type: "constant"
      value: 1
    }
  }
}

Now, I know what lr_mult and decay_mult do, but I fail to understand why they are defined twice. Can someone help?

[Fabio Maria Carlucci]

I'll answer myself, the first one appears to be for the filters and the second one for the biases. I must say it is not self evident, imo.