fixedHajnal.twoz_es: Fixed-design two-sample z-tests with NAP for varied sample...
In NAP: Non-Local Alternative Priors in Psychology

Description Usage Arguments Value Author(s) References Examples

In two-sided fixed design two-sample z-tests with composite alternative prior assumed on the difference between standardized effect sizes (μ_2 - μ_1)/σ_0 under the alternative, this function calculates the expected log(Hajnal's ratio) at a prefixed standardized effect size for a varied range of sample sizes.

fixedHajnal.twoz_es(es = 0, es1 = 0.3, n1min = 20, n2min = 20, 
                    n1max = 5000, n2max = 5000, sigma0 = 1, 
                    batch1.size.increment, batch2.size.increment, 
                    nReplicate = 50000)

`es`	Numeric. Difference between standardized effect sizes where the expected weights of evidence is desired. Default: `0`.
`es1`	Positive numeric. δ as above. Default: 0.3. For this, the prior on (μ_2 - μ_1)/σ_0 takes values 0.3 and -0.3 each with equal probability 1/2.
`n1min`	Positive integer. Minimum sample size from Grpup-1 to be considered. Default: 20.
`n2min`	Positive integer. Minimum sample size from Grpup-2 to be considered. Default: 20.
`n1max`	Positive integer. Maximum sample size from Grpup-1 to be considered. Default: 5000.
`n2max`	Positive integer. Maximum sample size from Grpup-2 to be considered. Default: 5000.
`sigma0`	Positive numeric. Known common standard deviation of the populations. Default: 1.
`batch1.size.increment`	Positive numeric. Increment in sample size from Group-1. The sequence of sample size thus considered from Group-1 for the fixed design test is from `n1min` to `n1max` with an increment of `batch1.size.increment`. Default: `function(narg){20}`. This means an increment of 20 samples from Group-1 at each step.
`batch2.size.increment`	Positive numeric. Increment in sample size from Group-2. The sequence of sample size thus considered from Group-2 for the fixed design test is from `n2min` to `n2max` with an increment of `batch2.size.increment`. Default: `function(narg){20}`. This means an increment of 20 samples from Group-2 at each step.
`nReplicate`	Positve integer. Number of replicated studies based on which the expected weights of evidence is calculated. Default: 50,000.

A list with two components named summary and BF.

$summary is a data frame with columns n containing the values of sample sizes and avg.logBF containing the expected log(Hajnal's ratios) at those values.

$BF is a matrix of dimension number of sample sizes considered by nReplicate. Each row contains the Hajnal's ratios at the corresponding sample size in nReplicate replicated studies.

Sandipan Pramanik and Valen E. Johnson

Hajnal, J. (1961). A two-sample sequential t-test.Biometrika, 48:65-75, [Article].

Schnuerch, M. and Erdfelder, E. (2020). A two-sample sequential t-test.Biometrika, 48:65-75, [Article].