diff --git a/NAMESPACE b/NAMESPACE
index f0dda5b..9e998d4 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -4,7 +4,6 @@ export(GeomToken)
 export(GeomTurn)
 export(add_lines)
 export(calculate_timing)
-export(check_quality)
 export(geom_token)
 export(geom_turn)
 export(init)
diff --git a/R/source_quality.R b/R/source_quality.R
deleted file mode 100644
index 83320da..0000000
--- a/R/source_quality.R
+++ /dev/null
@@ -1,40 +0,0 @@
-#' Check the quality of a specific source
-#'
-#' Quality measure that is considered: the total duration of utterances in ms
-#' must not be equal to the number of utterances.
-#'
-#' @param data dataset including the columns source, begin, and end
-#' @param source the source that is verified
-#'
-#' @return 0 if the quality is good, 1 if the quality is bad
-#' @export
-check_quality <- function(data, source){
-  check_columns(data, c("source", "begin", "end"))
-
-  # extract only the source we want to check
-  data <- data[data$source == source,]
-  if(nrow(data) == 0){
-    stop(paste("Source", source, "not found in dataset."))
-  }
-
-  # number of utterances
-  nturns <- nrow(data)
-
-  # duration of spoken utterances
-  data$duration <- data$end - data$begin
-  total_duration <- sum(data$duration, na.rm = TRUE)
-
-  # if the total number of utterances is the same as the length of the spoken utterances
-  # that means that they all last one millisecond on average
-  # this is a sign of bad quality
-  quality <- ifelse(total_duration == nturns, 0, 1)
-
-  if(quality == 0){
-    cat(paste("WARNING: Bad data quality for source", source, "\n"))
-  }
-
-  return(quality)
-}
-
-
-
diff --git a/man/check_quality.Rd b/man/check_quality.Rd
deleted file mode 100644
index bf2d173..0000000
--- a/man/check_quality.Rd
+++ /dev/null
@@ -1,20 +0,0 @@
-% Generated by roxygen2: do not edit by hand
-% Please edit documentation in R/source_quality.R
-\name{check_quality}
-\alias{check_quality}
-\title{Check the quality of a specific source}
-\usage{
-check_quality(data, source)
-}
-\arguments{
-\item{data}{dataset including the columns source, begin, and end}
-
-\item{source}{the source that is verified}
-}
-\value{
-0 if the quality is good, 1 if the quality is bad
-}
-\description{
-Quality measure that is considered: the total duration of utterances in ms
-must not be equal to the number of utterances.
-}
diff --git a/vignettes/original_demo.Rmd b/vignettes/original_demo.Rmd
deleted file mode 100644
index 7175209..0000000
--- a/vignettes/original_demo.Rmd
+++ /dev/null
@@ -1,64 +0,0 @@
----
-title: "original_demo"
-output: rmarkdown::html_vignette
-vignette: >
-  %\VignetteIndexEntry{original_demo}
-  %\VignetteEngine{knitr::rmarkdown}
-  %\VignetteEncoding{UTF-8}
----
-
-```{r, include = FALSE}
-knitr::opts_chunk$set(
-  collapse = TRUE,
-  comment = "#>"
-)
-```
-
-library(convplot)
-
-
-# Sample data for ElPaCo eScience project
-# MD 202302
-
-
-
-# Packages & functions ----------------------------------------------------
-
-# Packages
-list.of.packages <- c("tidyverse","ggthemes","ggrepel","knitr","data.table","viridis","ggridges","cowplot")
-new.packages <- list.of.packages[!(list.of.packages %in% installed.packages()[,"Package"])]
-if(length(new.packages)) install.packages(new.packages)
-lapply(list.of.packages, require, character.only=T)
-
-# Load functions
-source("helper-functions.R")
-
-
-# Load data ---------------------------------------------------------------
-
-# subset of six languages and 5 source files per language
-# originates in: elpaco-lingdiv-branch-escience.R
-d <- read_csv("data/d_sample.csv")
-
-# metadata of corpora included in sample
-d.metadata <- read_csv("data/d_sample_metadata.csv")
-
-# tokenized data (generated using white space tokenizer without further assumptions)
-d.tokens <- read_csv("data/d_sample_tokens.csv")
-
-
-# Quick demo of existing code ---------------------------------------------
-
-# Warts and all!
-
-# inspect_corpus(): a quick quantitative + qualitative peek at a corpus
-# Liesenfeld & Dingemanse LREC
-
-inspect_corpus(lang="dutch")
-inspect_corpus(lang="siwu")
-
-# convplot(): function to display time-aligned 'piano roll' style plot of a conversation
-# Dingemanse & Liesenfeld ACL
-
-convplot(n=10,content=T,dyads=T)
-