ADDIS_spending: ADDIS-spending: Adaptive discarding algorithm for online FWER...

In dsrobertson/onlineFDR: Online error rate control

ADDIS-spending: Adaptive discarding algorithm for online FWER control

Description

Implements the ADDIS algorithm for online FWER control, where ADDIS stands for an ADaptive algorithm that DIScards conservative nulls, as presented by Tian and Ramdas (2021). The procedure compensates for the power loss of Alpha-spending, by including both adaptivity in the fraction of null hypotheses and the conservativeness of nulls.

Usage

ADDIS_spending(
  d,
  alpha = 0.05,
  gammai,
  lambda = 0.25,
  tau = 0.5,
  dep = FALSE,
  display_progress = FALSE
)

Arguments

d	Either a vector of p-values, or a dataframe with three columns: an identifier (‘id’), p-value (‘pval’), and lags (‘lags’).
alpha	Overall significance level of the procedure, the default is 0.05.
gammai	Optional vector of \gamma_i. A default is provided with \gamma_j proportional to 1/j^(1.6).
lambda	Optional parameter that sets the threshold for ‘candidate’ hypotheses. Must be between 0 and 1, defaults to 0.25.
tau	Optional threshold for hypotheses to be selected for testing. Must be between 0 and 1, defaults to 0.5.
dep	Logical. If TRUE runs the version for locally dependent p-values
display_progress	Logical. If TRUE prints out a progress bar for the algorithm runtime.

Details

The function takes as its input either a vector of p-values, or a dataframe with three columns: an identifier (‘id’), p-value (‘pval’), and lags, if the dependent version is specified (see below). Given an overall significance level \alpha, ADDIS depends on constants \lambda and \tau, where \lambda < \tau. Here \tau \in (0,1) represents the threshold for a hypothesis to be selected for testing: p-values greater than \tau are implicitly ‘discarded’ by the procedure, while \lambda \in (0,1) sets the threshold for a p-value to be a candidate for rejection: ADDIS-spending will never reject a p-value larger than \lambda. The algorithms also require a sequence of non-negative non-increasing numbers \gamma_i that sum to 1.

The ADDIS-spending procedure provably controls the FWER in the strong sense for independent p-values. Note that the procedure also controls the generalised familywise error rate (k-FWER) for k > 1 if \alpha is replaced by min(1, k\alpha).

Tian and Ramdas (2021) also presented a version for handling local dependence. More precisely, for any t>0 we allow the p-value p_t to have arbitrary dependence on the previous L_t p-values. The fixed sequence L_t is referred to as ‘lags’, and is given as the input lags for this version of the ADDIS-spending algorithm.

Further details of the ADDIS-spending algorithms can be found in Tian and Ramdas (2021).

Value

out	A dataframe with the original p-values pval, the adjusted testing levels \alpha_i and the indicator function of discoveries R. Hypothesis i is rejected if the i-th p-value is less than or equal to \alpha_i, in which case R[i] = 1 (otherwise R[i] = 0).

References

Tian, J. and Ramdas, A. (2021). Online control of the familywise error rate. Statistical Methods for Medical Research 30(4):976–993.

See Also

ADDIS provides online control of the FDR.

Examples

sample.df <- data.frame(
id = c('A15432', 'B90969', 'C18705', 'B49731', 'E99902',
    'C38292', 'A30619', 'D46627', 'E29198', 'A41418',
    'D51456', 'C88669', 'E03673', 'A63155', 'B66033'),
pval = c(2.90e-08, 0.06743, 0.01514, 0.08174, 0.00171,
        3.60e-05, 0.79149, 0.27201, 0.28295, 7.59e-08,
        0.69274, 0.30443, 0.00136, 0.72342, 0.54757),
lags = rep(1,15))

ADDIS_spending(sample.df) #independent

ADDIS_spending(sample.df, dep = TRUE) #Locally dependent

dsrobertson/onlineFDR documentation built on April 21, 2023, 8:17 p.m.