Fix noise_std computation in analysis

analysis/parameter_tuning.py

@@ -140,7 +140,7 @@ def _find_candidate_parameters(
     max_sum_per_partition_bounds = min_sum_per_partition_bounds = None
 
     if calculate_sum_per_partition_param:
-        if hist.linf_sum_contributions_histogram.bins[0].lower >= 0:
+        if hist.linf_sum_contributions_histogram.bins[0].lower < 0:
             logging.warning(
                 "max_sum_per_partition should not contain negative sums because"
                 " min_sum_per_partition tuning is not supported yet and "

analysis/per_partition_combiners.py

@@ -279,6 +279,10 @@ def compute_metrics(self, acc: AccumulatorType) -> metrics.SumMetrics:
             std_noise=std_noise,
             noise_kind=self._params.aggregate_params.noise_kind)
 
+    def get_sensitivities(self) -> dp_computations.Sensitivities:
+        return dp_computations.compute_sensitivities_for_sum(
+            self._params.aggregate_params)
+
 
 class CountCombiner(SumCombiner):
     """A combiner for utility analysis counts."""
@@ -298,6 +302,10 @@ def create_accumulator(
         self._params.aggregate_params.max_sum_per_partition = self._params.aggregate_params.max_contributions_per_partition
         return super().create_accumulator(data)
 
+    def get_sensitivities(self) -> dp_computations.Sensitivities:
+        return dp_computations.compute_sensitivities_for_count(
+            self._params.aggregate_params)
+
 
 class PrivacyIdCountCombiner(SumCombiner):
     """A combiner for utility analysis privacy ID counts."""
@@ -319,6 +327,10 @@ def create_accumulator(
         self._params.aggregate_params.max_sum_per_partition = 1.0
         return super().create_accumulator(data)
 
+    def get_sensitivities(self) -> dp_computations.Sensitivities:
+        return dp_computations.compute_sensitivities_for_privacy_id_count(
+            self._params.aggregate_params)
+
 
 class RawStatisticsCombiner(UtilityAnalysisCombiner):
     """A combiner for computing per-partition raw statistics (count etc)."""
@@ -335,6 +347,9 @@ def compute_metrics(self, acc: AccumulatorType):
         privacy_id_count, count = acc
         return metrics.RawStatistics(privacy_id_count, count)
 
+    def get_sensitivities(self) -> dp_computations.Sensitivities:
+        raise NotImplementedError("It's DP mechanism.")
+
 
 class CompoundCombiner(pipeline_dp.combiners.CompoundCombiner):
     """Compound combiner for Utility analysis per partition metrics."""

pipeline_dp/combiners.py

@@ -150,16 +150,16 @@ class CombinerParams:
 
     def __init__(self, spec: budget_accounting.MechanismSpec,
                  aggregate_params: pipeline_dp.AggregateParams):
-        self._mechanism_spec = spec
+        self.mechanism_spec = spec
         self.aggregate_params = copy.copy(aggregate_params)
 
     @property
     def eps(self):
-        return self._mechanism_spec.eps
+        return self.mechanism_spec.eps
 
     @property
     def delta(self):
-        return self._mechanism_spec.delta
+        return self.mechanism_spec.delta
 
     @property
     def scalar_noise_params(self):