Of limited interest to most users, the zeta function plays an internal role in 2-sample and stratified sensitivity analyses. The zeta function is equation (8), page 495, in Rosenbaum and Krieger (1990).
zeta(bigN, n, m, g)
Arguments
bigN: Total sample size in this stratum.
n: Treated sample size in this stratum.
m: The number of 1's in the vector u of unobserved covariates. Here, u has bigN-m 0's followed by m 1's.
g: The sensitivity parameter Γ, where Γ≥1.
Returns
The value of the zeta function.
References
Rosenbaum, P. R. and Krieger, A. M. (1990). Sensitivity of two-sampler permutation inferences in observational studies. Journal of the American Statistical Association, 85, 493-498.
Rosenbaum, P. R. (2002). Observational Studies (2nd edition). New York: Springer. Section 4.6.