diff --git a/R/highcharter-helper.R b/R/highcharter-helper.R
index c9c9ac1..76ebdc7 100644
--- a/R/highcharter-helper.R
+++ b/R/highcharter-helper.R
@@ -33,25 +33,25 @@
 #'   hc_freq_by_year_ci()
 #' }
 #'
-hc_freq_by_year_ci <- function(df, as.alternatives = F, ylabel = if(as.alternatives) "%" else "ipm") {
+hc_freq_by_year_ci <- function(df, as.alternatives = FALSE, ylabel = if(as.alternatives) "%" else "ipm") {
   title <- ""
   df <- df %>%
     { if(! as.alternatives) ipm(.) else RKorAPClient::percent(.) }
 
   if (!"year" %in% colnames(df)) {
-    df <- df %>% mutate(year = as.integer(queryStringToLabel(df$vc, pubDateOnly = T)))
+    df <- df %>% mutate(year = as.integer(queryStringToLabel(df$vc, pubDateOnly = TRUE)))
   }
   if (!"condition" %in% colnames(df)) {
     if (length(base::unique(df$query)) > 1) {
       df <- df %>% mutate(condition = query)
-      if(length(base::unique(queryStringToLabel(df$vc, excludePubDate = T ))) > 1) {
+      if(length(base::unique(queryStringToLabel(df$vc, excludePubDate = TRUE ))) > 1) {
         df <- df %>% mutate(condition = paste(condition, " & ",
-                                              queryStringToLabel(vc, excludePubDate = T )))
+                                              queryStringToLabel(vc, excludePubDate = TRUE )))
       }
     } else {
       title <- base::unique(df$query)
-      if(length(base::unique(queryStringToLabel(df$vc, excludePubDate = T ))) > 1) {
-        df <- df %>% mutate(condition = queryStringToLabel(vc, excludePubDate = T ))
+      if(length(base::unique(queryStringToLabel(df$vc, excludePubDate = TRUE ))) > 1) {
+        df <- df %>% mutate(condition = queryStringToLabel(vc, excludePubDate = TRUE ))
       }
     }
   }
@@ -66,17 +66,17 @@
       floor = 0,
       labels = if(as.alternatives) list(format = paste0("{value}\U2009", ylabel)) else NULL
     ) %>%
-    hc_xAxis(allowDecimals=F) %>%
+    hc_xAxis(allowDecimals=FALSE) %>%
     hc_add_theme(hc_theme_google(colors=palette)) %>%
     hc_plotOptions(
-      series = list(enabled = T),
+      series = list(enabled = TRUE),
       line = list(cursor = 'pointer', point = list(events = list(
         click = JS("function() { window.open(this.click, 'korap'); }")
       )))) %>%
-    hc_credits(enabled = T,
+    hc_credits(enabled = TRUE,
                text = "KorAP R Client Pakckage",
                href = "//github.com/KorAP/RKorAPClient/") %>%
-    hc_exporting(enabled = T) %>%
+    hc_exporting(enabled = TRUE) %>%
     hc_tooltip(
       formatter = JS(paste0("function (tooltip) {
         var str = tooltip.defaultFormatter.call(this, tooltip);
@@ -88,9 +88,9 @@
        }
        return str.replace(/@/g, '", ylabel, "')
       } ")),
-      crosshairs =  T,
+      crosshairs =  TRUE,
       valueDecimals = 2,
-      shared = T,
+      shared = TRUE,
       valueSuffix = paste0('\U2009', ylabel)
     ) %>%
     hc_add_series_korap_frequencies(df, as.alternatives)
@@ -99,7 +99,7 @@
 ## Mute notes: "no visible binding for global variable:"
 globalVariables(c("value", "query", "condition", "vc"))
 
-hc_add_series_korap_frequencies <- function(hc, df, as.alternatives = F) {
+hc_add_series_korap_frequencies <- function(hc, df, as.alternatives = FALSE) {
   index <- 0
   for(q in unique(df$condition)) {
     dat <- df[df$condition==q,]
@@ -124,8 +124,8 @@
         type = 'arearange',
         fillOpacity = 0.3,
         lineWidth = 0,
-        marker = list(enabled = F),
-        enableMouseTracking = F,
+        marker = list(enabled = FALSE),
+        enableMouseTracking = FALSE,
         linkedTo= ':previous',
         colorIndex = index,
         zIndex = 0
diff --git a/R/misc.R b/R/misc.R
index 75697d3..a39ef21 100644
--- a/R/misc.R
+++ b/R/misc.R
@@ -26,7 +26,7 @@
 #' Convert corpus frequency table of alternatives to percent
 #'
 #' Convenience function for converting frequency tables of alternative variants
-#' (generated with \code{as.alternatives=T}) to percent.
+#' (generated with \code{as.alternatives=TRUE}) to percent.
 #'
 #' @param df table returned from \code{\link{frequencyQuery}}
 #'
@@ -67,7 +67,7 @@
 #' @importFrom PTXQC lcsCount
 #'
 #' @export
-queryStringToLabel <- function(data, pubDateOnly = F, excludePubDate = F) {
+queryStringToLabel <- function(data, pubDateOnly = FALSE, excludePubDate = FALSE) {
   if (pubDateOnly) {
     data <-substring(data, regexpr("pubDate", data)+7)
   } else if(excludePubDate) {
diff --git a/demo/highcharter-example.R b/demo/highcharter-example.R
index 4d312ba..e2947ea 100644
--- a/demo/highcharter-example.R
+++ b/demo/highcharter-example.R
@@ -4,7 +4,7 @@
                           years = c(2000:2010),
                           as.alternatives = length(query) > 1,
                           vc = "textType = /Zeit.*/ & availability!=QAO-NC-LOC:ids & pubDate in",
-                          kco = new("KorAPConnection", verbose=T) ) {
+                          kco = new("KorAPConnection", verbose=TRUE) ) {
   hc <-
     frequencyQuery(kco, query, paste(vc, years), as.alternatives=as.alternatives) %>%
     hc_freq_by_year_ci(as.alternatives)
@@ -13,11 +13,11 @@
 }
 
 saveHCPlot <- function(hc, fname) {
-  htmlwidgets::saveWidget(hc, file=fname, selfcontained = T)
+  htmlwidgets::saveWidget(hc, file=fname, selfcontained = TRUE)
 }
 
 #h1 <-plotHighchart(c("macht []{0,3} Sinn", "ergibt []{0,3} Sinn"), c(1980:2018))
-h1 <- plotHighchart(c("Leser | Lesern | Lesers", 'Leserin | Leserinnen', 'LeserIn | LeserInnen', '"Leser[_\\*]in.*"'), c(1985:2018), as.alternatives = F)
+h1 <- plotHighchart(c("Leser | Lesern | Lesers", 'Leserin | Leserinnen', 'LeserIn | LeserInnen', '"Leser[_\\*]in.*"'), c(1985:2018), as.alternatives = FALSE)
 #plotHighchart(c("Tollpatsch", "Tolpatsch"), c(1991:2018))
 
 
diff --git a/demo/writtenVsSpoken.R b/demo/writtenVsSpoken.R
index 6e63399..87b93b4 100644
--- a/demo/writtenVsSpoken.R
+++ b/demo/writtenVsSpoken.R
@@ -2,7 +2,7 @@
 # install_github("KorAP/RKorAPClient")
 library(RKorAPClient)
 library(ggplot2)
-g <- new("KorAPConnection", verbose=T) %>%
+g <- new("KorAPConnection", verbose=TRUE) %>%
   frequencyQuery("sozusagen/i", vc=c("corpusSigle=FOLK", "corpusSigle!=FOLK")) %>%
   ipm() %>%
   mutate(corpus=c("FOLK", "DeReKo")) %>%
diff --git a/man/hc_freq_by_year_ci.Rd b/man/hc_freq_by_year_ci.Rd
index d50dab0..273b06f 100644
--- a/man/hc_freq_by_year_ci.Rd
+++ b/man/hc_freq_by_year_ci.Rd
@@ -6,7 +6,7 @@
 \usage{
 hc_freq_by_year_ci(
   df,
-  as.alternatives = F,
+  as.alternatives = FALSE,
   ylabel = if (as.alternatives) "\%" else "ipm"
 )
 }
diff --git a/man/percent.Rd b/man/percent.Rd
index 13a1673..1e40204 100644
--- a/man/percent.Rd
+++ b/man/percent.Rd
@@ -14,7 +14,7 @@
 }
 \description{
 Convenience function for converting frequency tables of alternative variants
-(generated with \code{as.alternatives=T}) to percent.
+(generated with \code{as.alternatives=TRUE}) to percent.
 }
 \examples{
 \donttest{
diff --git a/man/queryStringToLabel.Rd b/man/queryStringToLabel.Rd
index 67d138c..8dedafe 100644
--- a/man/queryStringToLabel.Rd
+++ b/man/queryStringToLabel.Rd
@@ -4,7 +4,7 @@
 \alias{queryStringToLabel}
 \title{Convert query or vc strings to plot labels}
 \usage{
-queryStringToLabel(data, pubDateOnly = F, excludePubDate = F)
+queryStringToLabel(data, pubDateOnly = FALSE, excludePubDate = FALSE)
 }
 \arguments{
 \item{data}{string or vector of query or vc definition strings}