`weighted_se()`

computes weighted standard errors of a variable or for
all variables of a data frame. `survey_median()`

computes the median for
a variable in a survey-design (see [`survey::svydesign()]`

).
`weighted_correlation()`

computes a weighted correlation for a two-sided
alternative hypothesis.

```
survey_median(x, design)
weighted_correlation(data, ...)
# S3 method for default
weighted_correlation(data, x, y, weights, ci.lvl = 0.95, ...)
# S3 method for formula
weighted_correlation(formula, data, ci.lvl = 0.95, ...)
weighted_se(x, weights = NULL)
```

- x
(Numeric) vector or a data frame. For

`survey_median()`

or`weighted_ttest()`

, the bare (unquoted) variable name, or a character vector with the variable name.- design
An object of class

`svydesign`

, providing a specification of the survey design.- data
A data frame.

- ...
Currently not used.

- y
Optional, bare (unquoted) variable name, or a character vector with the variable name.

- weights
Bare (unquoted) variable name, or a character vector with the variable name of the numeric vector of weights. If

`weights = NULL`

, unweighted statistic is reported.- ci.lvl
Confidence level of the interval.

- formula
A formula of the form

`lhs ~ rhs1 + rhs2`

where`lhs`

is a numeric variable giving the data values and`rhs1`

a factor with two levels giving the corresponding groups and`rhs2`

a variable with weights.

The weighted (test) statistic.

```
data(efc)
weighted_se(efc$c12hour, abs(runif(n = nrow(efc))))
#> [1] 6.811783
# survey_median ----
# median for variables from weighted survey designs
data(nhanes_sample)
des <- survey::svydesign(
id = ~SDMVPSU,
strat = ~SDMVSTRA,
weights = ~WTINT2YR,
nest = TRUE,
data = nhanes_sample
)
survey_median(total, des)
#> $total
#> 0.5
#> [1,] 6
#>
#> attr(,"hasci")
#> [1] FALSE
#> attr(,"class")
#> [1] "newsvyquantile"
survey_median("total", des)
#> $total
#> 0.5
#> [1,] 6
#>
#> attr(,"hasci")
#> [1] FALSE
#> attr(,"class")
#> [1] "newsvyquantile"
```