report_row.proto

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
syntax = "proto3";

package cobalt;

import "observation_batch.proto";

// A row of output for a report of type SimpleOccurrenceCount. Gives the total
// daily, fleet-wide count of the number of occurrences of a single event type,
// on a single day, considering only devices matching a single system profile.
message SimpleOccurrenceCountReportRow {
  // The date on which the logged events occurred, as measured on the device.
  // This is a string in yyyy-mm-dd format.
  string date = 1;

  // A profile of the system from which the events were logged. This will be
  // populated with only the fields that are specified in the
  // |system_profile_field| entry in the ReportDefinition for this report.
  SystemProfile system_profile = 2;

  // The name of the event type. If the event_type_index has not been assigned
  // a name (in the event_types field of the MetricDefinition) then this will
  // be a string of the form "<index=42>".
  string event_type = 3;

  // The total count of the event occurrence on the |date|, over all reporting
  // devices with the |system_profile|. Unless |local_privacy_noise_level| in
  // the Reportdefintion is set to NONE, this value is an estimate.
  float count = 4;

  // An estimate of the standard error in the value of the |count|. This will
  // be zero if |local_privacy_noise_level| in the Reportdefintion is NONE.
  // Multiply this value by z_{alpha/2} to obtain the radius of an approximate
  // 100(1 - alpha)% confidence interval. For example an approximate 95%
  // confidence interval for the count is given by
  // (count_estimate - 1.96*std_error, count_estimate + 1.96 * std_error)
  // because 1.96 ~= z_{.025} meaning that P(Z > 1.96) ~= 0.025 where
  // Z ~ Normal(0, 1).
  float std_err = 5;
}