CDF of Marginal K Distribution
cdf_K_marginal.RdComputes the cumulative distribution function \(P(K_J \leq k \mid a, b)\) for \(k = 0, 1, \ldots, J\).
Usage
cdf_K_marginal(
J,
a,
b,
logS,
M = .QUAD_NODES_DEFAULT,
M_verify = NULL,
abs_tol = 1e-10,
rel_tol = 1e-08,
strict = FALSE
)Arguments
- J
Integer; sample size.
- a
Numeric; shape parameter of Gamma prior (> 0).
- b
Numeric; rate parameter of Gamma prior (> 0).
- logS
Matrix; pre-computed log-Stirling matrix.
- M
Integer; number of quadrature nodes (default: 80).
- M_verify
Optional independent order satisfying the package verification rule (at least
max(2*M, M+40)).- abs_tol, rel_tol
Non-negative selected-versus-verification tolerances.
- strict
Logical; require successful higher-order verification.
Value
Numeric vector of length \(J+1\) containing
\(P(K_J \leq k \mid a, b)\) for \(k = 0, 1, \ldots, J\).
The vector carries the PMF's "marginal_metadata" attribute.
Details
The CDF satisfies:
\(F(0) = 0\) (since \(P(K_J = 0) = 0\))
\(F(J) = 1\)
\(F(k)\) is non-decreasing in \(k\)
Examples
logS <- compute_log_stirling(50)
cdf <- cdf_K_marginal(50, 1.5, 0.5, logS)
# Verify CDF ends at 1
cdf[51]
#> [1] 1
# P(K <= 10)
cdf[11]
#> [1] 0.7009381