RAPPOR implementation

components/rappor/rappor_parameters.h

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_RAPPOR_RAPPOR_PARAMETERS_H_
+#define COMPONENTS_RAPPOR_RAPPOR_PARAMETERS_H_
+
+#include <string>
+
+namespace rappor {
+
+enum Probability {
+  PROBABILITY_87_5,  // 87.5%
+  PROBABILITY_75,    // 75%
+  PROBABILITY_50,    // 50%
+  PROBABILITY_25,    // 25%
+  PROBABILITY_12_5,  // 12.5%
+};
+
+// An object describing a rappor metric and the parameters used to generate it.
+//
+// For a full description of the rappor metrics, see
+// http://www.chromium.org/developers/design-documents/rappor
+struct RapporParameters {
+  // The name of the metric.
+  std::string rappor_name;
+
+  // The number of bytes stored in the bloom filter.
+  int bloom_filter_size_bytes;
+  // The number of hashes used in the bloom filter.
+  int bloom_filter_hash_count;
+
+  // The probability that a bit will be replaced with fake data.
+  Probability fake_prob;
+  // The probability that a fake bit will be a one.
+  Probability fake_one_prob;
+  // The probability that a one bit reports as one.

[Ilya Sherman, 2014/01/10 11:00:32]

nit: Is this a true one bit, or any one bit, after the fakes have been
substituted?

[Steven Holte, 2014/01/14 00:47:54]

Done.

+  Probability one_coin_prob;
+  // The probability that a zero bit reports as one.

[Ilya Sherman, 2014/01/10 11:00:32]

Ditto

[Steven Holte, 2014/01/14 00:47:54]

Done.

+  Probability zero_coin_prob;
+};

[Ilya Sherman, 2014/01/10 11:00:32]

nit: Should all of the fields in this struct be marked as const, or is that
overkill, do you think?

[Steven Holte, 2014/01/14 00:47:54]

I don't think that would be meaningful, since the same thing is accomplished by
making the instance of the object const.

+
+}  // namespace rappor
+
+#endif  // COMPONENTS_RAPPOR_RAPPOR_PARAMETERS_H_