Struct opendp::metrics::SymmetricDistance

pub struct SymmetricDistance;

The smallest number of additions or removals to make two datasets equivalent.

This metric is not sensitive to data ordering. Because this metric counts additions and removals, it is an unbounded metric (for unbounded DP).

Proof Definition

d-closeness

For any two vectors $u, v \in \texttt{D}$ and any $d$ of type IntDistance, we say that $u, v$ are $d$-close under the symmetric distance metric (abbreviated as $d_{Sym}$) whenever

d_{Sym}(u, v) = |u \Delta v| \leq d

Note

The distance type is hard-coded as IntDistance, so this metric is not generic over the distance type like many other metrics.

Compatible Domains

• VectorDomain<D> for any valid D

When this metric is paired with a VectorDomain, we instead consider the multisets corresponding to $u, v \in \texttt{D}$.

Trait Implementations

impl Clone for SymmetricDistance

fn clone(&self) -> SymmetricDistance

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SymmetricDistance

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for SymmetricDistance

fn default() -> Self

Returns the “default value” for a type.

impl Metric for SymmetricDistance

type Distance = u32

Proof Definition

impl PartialEq<SymmetricDistance> for SymmetricDistance

fn eq(&self, _other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl UnboundedMetric for SymmetricDistance

type BoundedMetric = ChangeOneDistance

impl UnorderedMetric for SymmetricDistance

type OrderedMetric = InsertDeleteDistance