Average Drawdown
PortfolioOptimisers.AverageDrawdown — Type
struct AverageDrawdown{__T_settings, __T_w} <: RiskMeasureRepresents the Average Drawdown risk measure.
AverageDrawdown computes the mean of the absolute drawdown series of the portfolio returns. It provides a measure of the average magnitude of drawdowns over the sample period.
Mathematical definition
Define the absolute drawdown series:
\[\begin{align} c_t &= \sum_{s=1}^{t} x_s\,, \\ d_t &= c_t - \max_{0 \leq s \leq t} c_s \leq 0\,. \end{align}\]
Where:
- $\boldsymbol{x}$: Portfolio returns vector $T \times 1$.
- $c_t$: Cumulative simple portfolio return at period $t$.
- $d_t \leq 0$: Absolute drawdown at period $t$.
The Average Drawdown is:
\[\begin{align} \mathrm{ADD}(\boldsymbol{x}) &= -\frac{1}{T} \sum_{t=1}^{T} d_t\,. \end{align}\]
Where:
- $\mathrm{ADD}(\boldsymbol{x})$: Average drawdown.
- $T$: Number of observations.
- $d_t \leq 0$: Absolute drawdown at period $t$.
For observation-weighted samples, the weighted mean is used instead.
Fields
settings: Risk measure settings.
w: Optional observation weights vectorobservations × 1, or a concrete subtype ofDynamicAbstractWeights. Ifnothing, the computation is unweighted.
Constructors
AverageDrawdown(; settings::RiskMeasureSettings = RiskMeasureSettings(), w::Option{<:ObsWeights} = nothing) -> AverageDrawdownKeywords correspond to the struct's fields.
Validation
- If
wis notnothing,!isempty(w).
Functor
(r::AverageDrawdown)(x::VecNum)Computes the Average Drawdown of a portfolio returns vector x.
Arguments
x::VecNum: Portfolio returns vector.
Examples
julia> AverageDrawdown()AverageDrawdown settings ┼ RiskMeasureSettings │ scale ┼ Float64: 1.0 │ ub ┼ nothing │ rke ┴ Bool: true w ┴ nothingRelated
RiskMeasureRiskMeasureSettingsMaximumDrawdownUlcerIndexConditionalDrawdownatRiskRelativeAverageDrawdownaverage_drawdown
References
- [102] A. Chekhlov, S. Uryasev and M. Zabarankin. Drawdown measure in portfolio optimization. International Journal of Theoretical and Applied Finance 8, 13–58 (2005).
PortfolioOptimisers.RelativeAverageDrawdown — Type
struct RelativeAverageDrawdown{__T_settings, __T_w} <: HierarchicalRiskMeasureRepresents the Relative Average Drawdown risk measure for hierarchical optimisation.
RelativeAverageDrawdown computes the mean of the relative (compounded) drawdown series of the portfolio returns.
Mathematical definition
Define the compounded wealth process and relative drawdown series:
\[\begin{align} C_t &= \prod_{s=1}^{t} (1 + x_s)\,, \\ rd_t &= \frac{C_t}{\max_{0 \leq s \leq t} C_s} - 1 \leq 0\,. \end{align}\]
Where:
- $\boldsymbol{x}$: Portfolio returns vector $T \times 1$.
- $C_t$: Compound wealth process at period $t$.
- $rd_t \leq 0$: Relative drawdown at period $t$.
The Relative Average Drawdown is:
\[\begin{align} \mathrm{RADD}(\boldsymbol{x}) &= -\frac{1}{T} \sum_{t=1}^{T} rd_t\,. \end{align}\]
Where:
- $\mathrm{RADD}(\boldsymbol{x})$: Relative average drawdown.
- $T$: Number of observations.
- $rd_t \leq 0$: Relative drawdown at period $t$.
For observation-weighted samples, the weighted mean is used instead.
Fields
settings: Risk measure settings.
w: Optional observation weights vectorobservations × 1, or a concrete subtype ofDynamicAbstractWeights. Ifnothing, the computation is unweighted.
Constructors
RelativeAverageDrawdown(; settings::HierarchicalRiskMeasureSettings = HierarchicalRiskMeasureSettings(), w::Option{<:ObsWeights} = nothing) -> RelativeAverageDrawdownKeywords correspond to the struct's fields.
Validation
- If
wis notnothing,!isempty(w).
Functor
(r::RelativeAverageDrawdown)(x::VecNum)Computes the Relative Average Drawdown of a portfolio returns vector x.
Arguments
x::VecNum: Portfolio returns vector.
Examples
julia> RelativeAverageDrawdown()RelativeAverageDrawdown settings ┼ HierarchicalRiskMeasureSettings │ scale ┴ Float64: 1.0 w ┴ nothingRelated
HierarchicalRiskMeasureHierarchicalRiskMeasureSettingsAverageDrawdownRelativeMaximumDrawdownaverage_drawdown
References
- [102] A. Chekhlov, S. Uryasev and M. Zabarankin. Drawdown measure in portfolio optimization. International Journal of Theoretical and Applied Finance 8, 13–58 (2005).
References
- [102]
- A. Chekhlov, S. Uryasev and M. Zabarankin. Drawdown measure in portfolio optimization. International Journal of Theoretical and Applied Finance 8, 13–58 (2005).