RMarkdown won't knit vcd datasets

[RStudentio]

Hi everyone,

A quick disclaimer: I'm pretty new to R, just in case some of what I'm about to ask sounds silly. Anyways, here's my problem:
I opened up a new RMarkdown file today and tried to execute some basic commands (summary, etc.) on the BrokenMarriage dataset from the vcd library. However, when I tried to knit my file an error message appeared:

It works perfectly fine with the "standard" datasets (trees, etc.) and executing these commands within a normal RScript file (on the BrokenMarriage dataset) also causes no problems. I have no clue what goes wrong here so I'd ber very thankfull for any advise.
Here 's the code I tried to run in case I'm missing something important:

Not run:

install.packages("vcd")
library("vcd")

summary(BrokenMarriage)

End(Not run)

[cderv]

Rendering this examples works for me

---
title: "test"
output: html_document
---

```{r}
library("vcd")
summary(BrokenMarriage)
```

What does not work for you ?

FAQ: How to Format R Markdown Source