`srvyr`

compared to the
`survey`

packageThe `srvyr`

package adds `dplyr`

like syntax to
the `survey`

package. This vignette focuses on how
`srvyr`

compares to the `survey`

package, for more
information about survey design and analysis, check out the vignettes in
the `survey`

package, or Thomas Lumley’s book, *Complex
Surveys: A Guide to Analysis Using R*. (Also see the bottom of
this document for some more resources).

Everything that `srvyr`

can do, can also be done in
`survey`

. In fact, behind the scenes the `survey`

package is doing all of the hard work for `srvyr`

.
`srvyr`

strives to make your code simpler and more easily
readable to you, especially if you are already used to the
`dplyr`

package.

The `dplyr`

package has made it easy to write code to
summarize data. For example, if we wanted to check how the year-to-year
change in academic progress indicator score varied by school level and
percent of parents were high school graduates, we can do this:

```
library(survey)
library(ggplot2)
library(dplyr)
data(api)
out <- apistrat %>%
mutate(hs_grad_pct = cut(hsg, c(0, 20, 100), include.lowest = TRUE,
labels = c("<20%", "20+%"))) %>%
group_by(stype, hs_grad_pct) %>%
summarize(api_diff = weighted.mean(api00 - api99, pw),
n = n())
ggplot(data = out, aes(x = stype, y = api_diff, group = hs_grad_pct, fill = hs_grad_pct)) +
geom_col(stat = "identity", position = "dodge") +
geom_text(aes(y = 0, label = n), position = position_dodge(width = 0.9), vjust = -1)
```

```
## Warning in geom_col(stat = "identity", position = "dodge"): Ignoring unknown
## parameters: `stat`
```

However, if we wanted to add error bars to the graph to capture the
uncertainty due to sampling variation, we have to completely rewrite the
`dplyr`

code for the `survey`

package.
`srvyr`

allows a more direct translation.

`as_survey_design()`

, `as_survey_rep()`

and
`as_survey_twophase()`

are analogous to
`survey::svydesign()`

, `survey::svrepdesign()`

and
`survey::twophase()`

respectively. Because they are designed
to match `dplyr`

’s style of non-standard evaluation, they
accept bare column names instead of formulas (~). They also move the
data argument first, so that it is easier to use `magrittr`

pipes (`%>%`

).

```
library(srvyr)
# simple random sample
srs_design_srvyr <- apisrs %>% as_survey_design(ids = 1, fpc = fpc)
srs_design_survey <- svydesign(ids = ~1, fpc = ~fpc, data = apisrs)
```

The `srvyr`

functions also accept
`dplyr::select()`

’s special selection functions (such as
`starts_with()`

, `one_of()`

, etc.), so these
functions are analogous:

```
# selecting variables to keep in the survey object (stratified example)
strat_design_srvyr <- apistrat %>%
as_survey_design(1, strata = stype, fpc = fpc, weight = pw,
variables = c(stype, starts_with("api")))
strat_design_survey <- svydesign(~1, strata = ~stype, fpc = ~fpc,
variables = ~stype + api99 + api00 + api.stu,
weight = ~pw, data = apistrat)
```

The function `as_survey()`

will automatically choose
between the three `as_survey_*`

functions based on the
arguments, so you can save a few keystrokes.

Once you’ve set up your survey data, you can use `dplyr`

verbs such as `mutate()`

, `select()`

,
`filter()`

and `rename()`

.

```
strat_design_srvyr <- strat_design_srvyr %>%
mutate(api_diff = api00 - api99) %>%
rename(api_students = api.stu)
strat_design_survey$variables$api_diff <- strat_design_survey$variables$api00 -
strat_design_survey$variables$api99
names(strat_design_survey$variables)[names(strat_design_survey$variables) == "api.stu"] <- "api_students"
```

Note that `arrange()`

is not available, because the
`srvyr`

object expects to stay in the same order. Nor are
two-table verbs such as `full_join()`

,
`bind_rows()`

, etc. available to `srvyr`

objects
either because they may have implications on the survey design. If you
need to use these functions, you should use them earlier in your
analysis pipeline, when the objects are still stored as
`data.frame`

s.

`srvyr`

also provides `summarize()`

and several
survey-specific functions that calculate summary statistics on numeric
variables: `survey_mean()`

, `survey_total()`

,
`survey_quantile()`

and `survey_ratio()`

. These
functions differ from their counterparts in `survey`

because
they always return a data.frame in a consistent format. As such, they do
not return the variance-covariance matrix, and so are not as
flexible.

```
# Using srvyr
out <- strat_design_srvyr %>%
summarize(api_diff = survey_mean(api_diff, vartype = "ci"))
out
```

```
## # A tibble: 1 × 3
## api_diff api_diff_low api_diff_upp
## <dbl> <dbl> <dbl>
## 1 32.9 28.8 36.9
```

```
## mean SE
## api_diff 32.893 2.0511
```

```
## 2.5 % 97.5 %
## api_diff 28.87241 36.91262
```

`srvyr`

also allows you to calculate statistics on numeric
variables by group, using `group_by()`

.

```
# Using srvyr
strat_design_srvyr %>%
group_by(stype) %>%
summarize(api_increase = survey_total(api_diff >= 0),
api_decrease = survey_total(api_diff < 0))
```

```
## # A tibble: 3 × 5
## stype api_increase api_increase_se api_decrease api_decrease_se
## <fct> <dbl> <dbl> <dbl> <dbl>
## 1 E 4067. 119. 354. 119.
## 2 H 498. 49.4 257. 49.4
## 3 M 998. 19.9 20.4 19.9
```

```
## stype api_diff >= 0FALSE api_diff >= 0TRUE se.api_diff >= 0FALSE
## E E 353.68 4067.32 119.17185
## H H 256.70 498.30 49.37208
## M M 20.36 997.64 19.85371
## se.api_diff >= 0TRUE
## E 119.17185
## H 49.37208
## M 19.85371
```

You can also calculate the proportion or count in each group of a
factor or character variable by leaving x empty in
`survey_mean()`

or `survey_total()`

.

```
# Using srvyr
srs_design_srvyr %>%
group_by(awards) %>%
summarize(proportion = survey_mean(),
total = survey_total())
```

```
## # A tibble: 2 × 5
## awards proportion proportion_se total total_se
## <fct> <dbl> <dbl> <dbl> <dbl>
## 1 No 0.38 0.0338 2354. 210.
## 2 Yes 0.62 0.0338 3840. 210.
```

```
## mean SE
## awardsNo 0.38 0.0338
## awardsYes 0.62 0.0338
```

```
## total SE
## awardsNo 2353.7 209.65
## awardsYes 3840.3 209.65
```

Finally, the `unweighted()`

function can act as an escape
hatch to calculate unweighted calculations on the dataset.

```
## # A tibble: 3 × 2
## stype n
## <fct> <int>
## 1 E 100
## 2 H 50
## 3 M 50
```

```
## stype counts se
## E E 100 0
## H H 50 0
## M M 50 0
```

So now, we have all the tools needed to create the first graph and
add error bounds. Notice that the data manipulation code is nearly
identical to the `dplyr`

code, with a little extra set up,
and replacing `weighted.mean()`

with
`survey_mean`

.

```
strat_design <- apistrat %>%
as_survey_design(strata = stype, fpc = fpc, weight = pw)
out <- strat_design %>%
mutate(hs_grad_pct = cut(hsg, c(0, 20, 100), include.lowest = TRUE,
labels = c("<20%", "20+%"))) %>%
group_by(stype, hs_grad_pct) %>%
summarize(api_diff = survey_mean(api00 - api99, vartype = "ci"),
n = unweighted(n()))
ggplot(data = out, aes(x = stype, y = api_diff, group = hs_grad_pct, fill = hs_grad_pct,
ymax = api_diff_upp, ymin = api_diff_low)) +
geom_col(stat = "identity", position = "dodge") +
geom_errorbar(position = position_dodge(width = 0.9), width = 0.1) +
geom_text(aes(y = 0, label = n), position = position_dodge(width = 0.9), vjust = -1)
```

```
## Warning in geom_col(stat = "identity", position = "dodge"): Ignoring unknown
## parameters: `stat`
```

For the most part, `srvyr`

tries to be a drop-in
replacement for the survey package, only changing the syntax that you
wrote. However, the way that calculations of degrees of freedom when
calculating confidence intervals is different.

`srvyr`

assumes that you want to use the true degrees of
freedom by default, but the `survey`

package uses
`Inf`

as the default. You can use the argument
`df`

to get the same result as the survey package.

```
# Set pillar print methods so tibble has more decimal places
old_sigfig <- options("pillar.sigfig")
options("pillar.sigfig" = 5)
# survey default
estimate <- svymean(~api99, strat_design)
confint(estimate)
```

```
## 2.5 % 97.5 %
## api99 609.8659 648.9238
```

```
## # A tibble: 1 × 3
## x x_low x_upp
## <dbl> <dbl> <dbl>
## 1 629.39 609.75 649.04
```

```
# setting the degrees of freedom so srvyr matches survey default
strat_design %>%
summarize(x = survey_mean(api99, vartype = "ci", df = Inf)) %>%
print()
```

```
## # A tibble: 1 × 3
## x x_low x_upp
## <dbl> <dbl> <dbl>
## 1 629.39 609.87 648.92
```

```
# setting the degrees of freedom so survey matches survey default
confint(estimate, df = degf(strat_design))
```

```
## 2.5 % 97.5 %
## api99 609.7452 649.0445
```

`survey`

functions on `srvyr`

objectsBecause `srvyr`

objects are just `survey`

objects with some extra structure, all of the functions from
`survey`

will still work with them. If you need to calculate
something beyond simple summary statistics, you can use
`survey`

functions.

```
##
## Call:
## svyglm(formula = api00 ~ ell + meals + mobility, design = strat_design)
##
## Survey design:
## Called via srvyr
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 820.8873 10.0777 81.456 <2e-16 ***
## ell -0.4806 0.3920 -1.226 0.222
## meals -3.1415 0.2839 -11.064 <2e-16 ***
## mobility 0.2257 0.3932 0.574 0.567
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## (Dispersion parameter for gaussian family taken to be 5171.966)
##
## Number of Fisher Scoring iterations: 2
```

Like `dplyr`

, `srvyr`

allows you to use
expressions in the arguments, allowing you to create variables in a
single step. For example, you can use expressions:

- as the arguments inside the survey statistic functions like
`survey_mean`

```
## # A tibble: 1 × 2
## prop_api99_over_700 prop_api99_over_700_se
## <dbl> <dbl>
## 1 0.306 0.0356
```

- as an argument to
`summarize`

```
## # A tibble: 2 × 3
## awards percentage percentage_se
## <fct> <dbl> <dbl>
## 1 No 36.1 3.44
## 2 Yes 63.9 3.44
```

- and you can even create variables inside of
`group_by`

```
strat_design %>%
group_by(api99_above_700 = api99 > 700) %>%
summarize(api00_mn = survey_mean(api00))
```

```
## # A tibble: 2 × 3
## api99_above_700 api00_mn api00_mn_se
## <lgl> <dbl> <dbl>
## 1 FALSE 599. 7.88
## 2 TRUE 805. 7.15
```

Though on-the-fly expressions are syntactically valid, it is possible to make statistically invalid numbers from them. For example, though the standard error and confidence intervals can be multiplied by a scalar (like 100), the variance does not scale the same way, so the following is invalid:

Srvyr supports the non-standard evaluation conventions that dplyr
uses. If you’d like to use a function programmatically, you can use the
functions from rlang like the `{{`

operator (aka “curly
curly”) from `rlang`

.

Here’s a quick example, but please see the dplyr vignette `vignette("programming", package = "dplyr")`

for more details.

```
mean_with_ci <- function(.data, var) {
summarize(.data, mean = survey_mean({{var}}, vartype = "ci"))
}
srs_design_srvyr <- apisrs %>% as_survey_design(fpc = fpc)
mean_with_ci(srs_design_srvyr, api99)
```

```
## # A tibble: 1 × 3
## mean mean_low mean_upp
## <dbl> <dbl> <dbl>
## 1 625. 606. 643.
```

Srvyr will also follow dplyr’s lead on deprecating the old methods of
NSE, such as `rlang::quo`

, and `!!`

, in addition
to the so-called “underscore functions” (like `summarize_`

).
Currently, they have been soft-deprecated, they may be removed
altogether in some future version of srvyr.

As of version 1.0 of srvyr, it supports dplyr’s across function, so
when you want to calculate a statistic on more than one variable, it is
easy to do so. See `vignette("colwise", package = "dplyr")`

for more details, but here is another quick example:

```
# Calculate survey mean for all variables that have names starting with "api"
strat_design %>%
summarize(across(starts_with("api"), survey_mean))
```

```
## # A tibble: 1 × 6
## api00 api00_se api99 api99_se api.stu api.stu_se
## <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 662. 9.41 629. 9.96 498. 16.1
```

Srvyr also supports older methods of working column-wise, the “scoped
variants”, such as `summarize_at`

, `summarize_if`

,
`summarize_all`

and `summarize_each`

. Again, these
are maintained for backwards compatibility, matching what the tidyverse
team has done, but may be removed from a future version.

You can calculate the weighted proportion that falls into a group
using the `survey_prop()`

function (or the
`survey_mean()`

function with no `x`

argument).
The proportion is calculated by “unpeeling” the last variable used in
`group_by()`

and then calculating the proportion within the
other groups that fall into the last group (so that the proportion
within each group that was unpeeled sums to 100%).

```
# Calculate the proportion that falls into each category of `awards` per `stype`
strat_design %>%
group_by(stype, awards) %>%
summarize(prop = survey_prop())
```

```
## When `proportion` is unspecified, `survey_prop()` now defaults to `proportion = TRUE`.
## ℹ This should improve confidence interval coverage.
## This message is displayed once per session.
```

```
## # A tibble: 6 × 4
## # Groups: stype [3]
## stype awards prop prop_se
## <fct> <fct> <dbl> <dbl>
## 1 E No 0.270 0.0441
## 2 E Yes 0.730 0.0441
## 3 H No 0.680 0.0644
## 4 H Yes 0.320 0.0644
## 5 M No 0.520 0.0696
## 6 M Yes 0.480 0.0696
```

If you want to calculate the proportion for groups from multiple
variables at the same time that add up to 100%, the
`interact`

function can help. The `interact`

function creates a variable that is automatically split apart so that
more than one variable can be unpeeled.

```
# Calculate the proportion that falls into each category of both `awards` and `stype`
strat_design %>%
group_by(interact(stype, awards)) %>%
summarize(prop = survey_prop())
```

```
## # A tibble: 6 × 4
## stype awards prop prop_se
## <fct> <fct> <dbl> <dbl>
## 1 E No 0.193 0.0315
## 2 E Yes 0.521 0.0315
## 3 H No 0.0829 0.00785
## 4 H Yes 0.0390 0.00785
## 5 M No 0.0855 0.0114
## 6 M Yes 0.0789 0.0114
```

Here are some free resources put together by the community about srvyr:

**“How-to”s & examples of using srvyr**- Stephanie Zimmer & Rebecca Powell’s 2021 AAPOR Workshop “Tidy Survey Analysis in R using the srvyr Package”
- “The Epidemiologist R Handbook”, by Neale Batra et al. has a chapter on survey analysis with srvyr and survey package examples
- Kieran Healy’s book “Data Visualization: A Practical Introduction” has a section on using srvyr to visualize the ESS.
- The IPUMS PMA team’s blog had a series showing examples of using the PMA COVID survey panel with weights
- “Open Case Studies: Vaping Behaviors in American Youth” by Carrie Wright, Michael Ontiveros, Leah Jager, Margaret Taub, and Stephanie Hicks is a detailed case study that includes using srvyr to analyze the National Youth Tobacco Survey.
- “How to plot Likert scales with a weighted survey in a dplyr friendly way” by Francisco Suárez Salas
- The tidycensus package vignette “Working with Census microdata” includes information about using the weights from the ACS retrieved from the census API.
- “The Joy of Calculating the Direct Standard Error for PUMS Estimates” by GitHub user @ldaly

**About survey statistics**- Thomas Lumley’s book “Complex Surveys: a guide to analysis using R”
- Chris Skinner. Jon Wakefield. “Introduction to the Design and Analysis of Complex Survey Data.” Statist. Sci. 32 (2) 165 - 175, May 2017. 10.1214/17-STS614
- Sharon Lohr’s textbook “Sampling: Design and Analysis”. Second or Third Editions
- “Survey weighting is a mess” is the opening to Andrew Gelman’s “Struggles with Survey Weighting and Regression Modeling”
- Anthony Damico’s website “Analyze Survey Data for Free” has the weight specifications for a wide variety of public use survey datasets.

**Working programmatically and/or on multiple columns at once (eg**`dplyr::across`

and`rlang`

’s “curly curly”`{{}}`

)- dplyr’s included package vignettes “Column-wise operations” & “Programming with dplyr”

**Non-English resources***Em português:*“Análise de Dados Amostrais Complexos” by Djalma Pessoa and Pedro Nascimento Silva*En español:*“Usando R para jugar con los microdatos del INEGI” by Claudio Daniel Pacheco Castro*Tiếng Việt:*“Dịch tễ học ứng dụng và y tế công cộng với R”

**Other cool stuff that uses srvyr**- A (free) graphical interface allowing exploratory data analysis of survey data without writing code: iNZight (and survey data instructions)
- “serosurvey: Serological Survey Analysis For Prevalence Estimation Under Misclassification” by Andree Valle Campos
- Several packages on CRAN depend on srvyr, you can see them by looking at the reverse Imports/Suggestions on CRAN.

**Still need help?**

I think the best way to get help is to form a specific question and ask it in some place like posit’s community website (known for it’s friendly community) or stackoverflow.com (maybe not known for being quite as friendly, but probably has more people). If you think you’ve found a bug in srvyr’s code, please file an issue on GitHub, but note that I’m not a great resource for helping specific issue, both because I have limited capacity but also because I do not consider myself an expert in the statistical methods behind survey analysis.

**Have something to add?**

These resources were mostly found via vanity searches on twitter & github. If you know of anything I missed, or have written something yourself, please let me know in this GitHub issue!