meanTest_func {EquiTrends} | R Documentation |
An internal function of the EquiTrends Mean Equivalence Testing procedure
Description
This is a supporting function of the meanEquivTest
function. It calculates the placebo coefficients and the absolute value of the mean of the placebo coefficients. It then calculates the critical value and p-values if an equivalence threshold is supplied for the test, according to Dette & Schumann (2024). If equivalence threshold is not supplied, it calculates the minimum equivalence threshold for which the null of non-negligible pre-trend differences can be rejected.
Usage
meanTest_func(
data,
equiv_threshold,
vcov,
cluster,
alpha,
n,
no_periods,
base_period,
is_panel_balanced
)
Arguments
data |
The data.frame object containing the data for the test. Should be of the form what is returned by the EquiTrends_dataconstr function. |
equiv_threshold |
The equivalence threshold for the test. If NULL, the minimum equivalence threshold for which the null hypothesis can be rejected is calculated. |
vcov |
The variance-covariance matrix estimator. See meanEquivTest for more information. |
cluster |
The cluster variable for the cluster-robust variance-covariance matrix estimator. See meanEquivTest for more information. |
alpha |
The significance level for the test. Only required if no equivalence threshold is supplied. |
n |
The number of cross-sectional individuals in the data. |
no_periods |
The number of periods in the data. |
base_period |
The base period for the test. Must be one of the unique periods in the data. |
is_panel_balanced |
A logical value indicating whether the panel data is balanced. |
Value
#' An object of class "meanEquivTest" containing:
placebo_coefficients |
A numeric vector of the estimated placebo coefficients, |
abs_mean_placebo_coefs |
the absolute value of the mean of the placebo coefficients, |
var_mean_placebo_coef |
the estimated variance of the mean placebo coefficient, |
significance_level |
the significance level of the test, |
num_individuals |
the number of cross-sectional individuals in the data, |
num_periods |
the number of periods in the data, |
base_period |
the base period in the data, |
num_observations |
the total number of observations in the data, |
equiv_threshold_specified |
a logical value indicating whether an equivalence threshold was specified. |
is_panel_balanced |
a logical value indicating whether the panel data is balanced. |
If is.null(equiv_threshold)
, then additionally minimum_equiv_threshold
: the minimum equivalence threshold for which the null hypothesis of non-negligible (based on the equivalence threshold) trend-differnces can be rejected.
if !(is.null(equiv_threshold))
, then additionally
-
mean_critical_value
: the critical value at the alpha level, -
p_value
: the p-value of the test, -
reject_null_hypothesis
: A logical value indicating whether to reject the null hypothesis, -
equiv_threshold
: the equivalence threshold specified.
References
Dette, H., & Schumann, M. (2024). "Testing for Equivalence of Pre-Trends in Difference-in-Differences Estimation." Journal of Business & Economic Statistics, 1–13. DOI: doi:10.1080/07350015.2024.2308121