R: Inclusion Probabilities: Stratified Random Sampling

strata_rs_probabilities {randomizr} | R Documentation

## Inclusion Probabilities: Stratified Random Sampling

### Description

Inclusion Probabilities: Stratified Random Sampling

### Usage

    strata_rs_probabilities(strata = NULL, prob = NULL, prob_unit = NULL,
      n = NULL, n_unit = NULL, strata_n = NULL, strata_prob = NULL,
      check_inputs = TRUE)

### Arguments

`strata` | A vector of length N that indicates which stratum each unit belongs to. Can be a character, factor, or numeric vector. (required)
`prob` | Use for a design in which either floor(N_stratum*prob) or ceiling(N_stratum*prob) units are sampled within each stratum. The probability of being sampled is exactly prob because with probability 1-prob, floor(N_stratum*prob) units will be sampled and with probability prob, ceiling(N_stratum*prob) units will be sampled. prob must be a real number between 0 and 1 inclusive. (optional)
`prob_unit` | Must of be of length N. tapply(prob_unit, strata, unique) will be passed to `strata_prob`.
`n` | Use for a design in which the scalar n describes the fixed number of units to sample in each stratum. This number does not vary across strata.
`n_unit` | Must be of length N. tapply(m_unit, strata, unique) will be passed to `strata_n`.
`strata_n` | Use for a design in which the numeric vector strata_n describes the number of units to sample within each stratum.
`strata_prob` | Use for a design in which strata_prob describes the probability of being sampled within each stratum. Differs from prob in that the probability of being sampled can vary across strata.
`check_inputs` | logical. Defaults to TRUE.

### Value

A vector length N indicating the probability of being sampled.

### Examples

    strata <- rep(c("A", "B","C"), times = c(50, 100, 200))
    probs <- strata_rs_probabilities(strata = strata)
    table(strata, probs)

    probs <- strata_rs_probabilities(strata = strata, prob = .2)
    table(strata, probs)

    probs <- strata_rs_probabilities(strata = strata, strata_prob = c(.1, .2, .3))
    table(strata, probs)

    probs <- strata_rs_probabilities(strata = strata, strata_n = c(10, 40, 70))
    table(strata, probs)

[Package randomizr version 0.18.0 Index]