This JSON object describes the hyperparameter search space, in the format required by Google Cloud Hypertune (https://cloud.google.com/ml-engine/reference/rest/v1/projects.jobs#HyperparameterSpec)

hyperparameter_spec.json

{
  "goal": "MINIMIZE",
  "params": [
    {
      "parameterName": "kernel-size-mel",
      "minValue": 2,
      "maxValue": 8,
      "type": "INTEGER"
    },
    {
      "parameterName": "kernel-size-time",
      "minValue": 2,
      "maxValue": 10,
      "type": "INTEGER"
    },
    {
      "parameterName": "pool-size-time",
      "minValue": 1,
      "maxValue": 10,
      "type": "INTEGER"
    },
    {
      "parameterName": "num-layers",
      "minValue": 4,
      "maxValue": 8,
      "type": "INTEGER"
    },
    {
      "parameterName": "num-units",
      "type": "DISCRETE",
      "discreteValues": [
        256,
        512
      ]
    },
    {
      "parameterName": "momentum",
      "minValue": 0.8,
      "maxValue": 0.99999,
      "type": "DOUBLE",
      "scaleType": "UNIT_LOG_SCALE"
    },
    {
      "parameterName": "lr",
      "minValue": 0.000001,
      "maxValue": 0.001,
      "type": "DOUBLE",
      "scaleType": "UNIT_LOG_SCALE"
    },
    {
      "parameterName": "dropout-rate",
      "minValue": 0.1,
      "maxValue": 0.5,
      "type": "DOUBLE",
      "scaleType": "UNIT_LINEAR_SCALE"
    },
    {
      "parameterName": "decay",
      "minValue": 0.00001,
      "maxValue": 0.1,
      "type": "DOUBLE",
      "scaleType": "UNIT_LOG_SCALE"
    },
    {
      "parameterName": "l2-regularization",
      "minValue": 0.0001,
      "maxValue": 0.1,
      "type": "DOUBLE",
      "scaleType": "UNIT_LOG_SCALE"
    }
  ],
  "maxTrials": 50,
  "maxParallelTrials": 3,
  "hyperparameterMetricTag": "val_binary_crossentropy",
  "enableTrialEarlyStopping": true
}