Inference for weighted inner product of the regression vectors in high dimensional generalized linear regressions

InnProd(
  X1,
  y1,
  X2,
  y2,
  G,
  A = NULL,
  model = c("linear", "logistic", "logistic_alter"),
  intercept = TRUE,
  beta.init1 = NULL,
  beta.init2 = NULL,
  split = TRUE,
  lambda = NULL,
  mu = NULL,
  prob.filter = 0.05,
  rescale = 1.1,
  tau = c(0.25, 0.5, 1),
  verbose = FALSE
)

Arguments

X1

Design matrix for the first sample, of dimension \(n_1\) x \(p\)

y1

Outcome vector for the first sample, of length \(n_1\)

X2

Design matrix for the second sample, of dimension \(n_2\) x \(p\)

y2

Outcome vector for the second sample, of length \(n_1\)

G

The set of indices, G in the quadratic form

A

The matrix A in the quadratic form, of dimension \(|G|\times\)\(|G|\). If NULL A would be set as the \(|G|\times\)\(|G|\) submatrix of the population covariance matrix corresponding to the index set G (default = NULL)

model

The high dimensional regression model, either "linear" or "logistic" or "logistic_alter"

intercept

Should intercept(s) be fitted for the initial estimators (default = TRUE)

beta.init1

The initial estimator of the regression vector for the 1st data (default = NULL)

beta.init2

The initial estimator of the regression vector for the 2nd data (default = NULL)

split

Sampling splitting or not for computing the initial estimators. It take effects only when beta.init1 = NULL or beta.init2 = NULL. (default = TRUE)

lambda

The tuning parameter in fitting initial model. If NULL, it will be picked by cross-validation. (default = NULL)

mu

The dual tuning parameter used in the construction of the projection direction. If NULL it will be searched automatically. (default = NULL)

prob.filter

The threshold of estimated probabilities for filtering observations in logistic regression. (default = 0.05)

rescale

The factor to enlarge the standard error to account for the finite sample bias. (default = 1.1)

tau

The enlargement factor for asymptotic variance of the bias-corrected estimator to handle super-efficiency. It allows for a scalar or vector. (default = c(0.25,0.5, 1))

verbose

Should intermediate message(s) be printed. (default = FALSE)

Value

est.plugin

The plugin(biased) estimator for the inner product form of the regression vectors restricted to G

est.debias

The bias-corrected estimator of the inner product form of the regression vectors

se

Standard errors of the bias-corrected estimator, length of tau; corrsponding to different values of tau

Examples

X1 <- matrix(rnorm(100 * 5), nrow = 100, ncol = 5)
y1 <- -0.5 + X1[, 1] * 0.5 + X1[, 2] * 1 + rnorm(100)
X2 <- matrix(rnorm(90 * 5), nrow = 90, ncol = 5)
y2 <- -0.4 + X2[, 1] * 0.48 + X2[, 2] * 1.1 + rnorm(90)
G <- c(1, 2)
A <- matrix(c(1.5, 0.8, 0.8, 1.5), nrow = 2, ncol = 2)
Est <- InnProd(X1, y1, X2, y2, G, A, model = "linear")

## compute confidence intervals
ci(Est, alpha = 0.05, alternative = "two.sided")
#>    tau    lower    upper
#> 1 0.25 1.578094 3.577448
#> 2 0.50 1.505050 3.650492
#> 3 1.00 1.358963 3.796579

## summary statistics
summary(Est)
#> Call: 
#> Inference for Inner Product
#> 
#>   tau est.plugin est.debias Std. Error z value  Pr(>|z|)    
#>  0.25      1.959      2.578     0.5100   5.054 4.327e-07 ***
#>  0.50      1.959      2.578     0.5473   4.710 2.479e-06 ***
#>  1.00      1.959      2.578     0.6219   4.145 3.394e-05 ***