diff --git a/README.md b/README.md
index 50f3082..28bdeab 100644
--- a/README.md
+++ b/README.md
@@ -157,7 +157,37 @@ dat_all[735, ]
 # 1427 2016_11_15-12_12_57.log 2016-12-15 12:12:57     850  Transform stop     076 076.xml   NA 2092.25 2008.00 0.2997107   13.26223362
 ```
 
-## Events that only close (`date.start` is NA)
+`time_ms` does not increase from log file to log file
+
+```{r}
+tmp1 <- dat[!duplicated(dat$fileid), c("fileid", "time_ms", "event")]
+tmp2 <- dat[!duplicated(dat$fileid, fromLast=T), c("fileid", "time_ms", "event")]
+tmp <- rbind(tmp1, tmp2)
+tmp <- tmp[order(tmp$fileid), ]
+head(tmp, 50)
+
+plot(time_ms ~ as.factor(fileid), dat[1:2000, ], xlab = "fileid")
+```
+
+## x,y-coordinates outside of display range
+
+The display is a 4K-display with 3840 x 2160 pixels. When you plot the
+start and stop coordinates, the display is clearly to distinguish. However,
+a lot of points are outside of the display range. This can happen, when the
+art objects are scaled and then moved to the very edge of the table. Then
+it will record pixels outside of the table. These are actually valid data
+points and I will leave them as is.
+
+```{r}
+par(mfrow = c(1, 2))
+plot(y.start ~ x.start, dat)
+abline(v = c(0, 3840), h = c(0, 2160), col = "blue", lwd = 2)
+plot(y.stop ~ x.stop, dat)
+abline(v = c(0, 3840), h = c(0, 2160), col = "blue", lwd = 2)
+
+
+aggregate(cbind(x.start, x.stop, y.start, y.stop) ~ 1, dat, mean)
+```
 
 
 ## Timestamps repeat
@@ -173,7 +203,44 @@ dat_all[735, ]
 
 ## Add moves to `trace` variable
 
+## openPopup does not close correctly
 
+The sorting had to include `popup` otherwise nested events could not be
+closed correctly.
+
+ ```{r}
+# TODO: Some correct entries are not closed:
+df[df$trace == 1843, ]
+# WHY???
+# --> Wrong eventid!
+dat5[dat5$trace == 1843, ]
+openPopup_wide[openPopup_wide$trace == 1843, ]
+```
+## Events that only close (`date.start` is NA)
+
+It looks like there is some kind of log error for the events that do not
+have a start stop. I was able to get rid of most by sorting for `popup` for
+the openPopup events, but there are still some left (50 for the small data
+set, which corresponds to 0.2 per mill).
+
+ ```{r}
+# remove all events that do not have a `date.start`
+dim(dat_all[is.na(dat_all$date.start), ])
+dat_all <- dat_all[!is.na(dat_all$date.start), ]
+# TODO: Find out how it can be that there is only a `date.stop`
+## --> happens, when event is not properly closed, see here:
+df[df$trace == 1843, ]
+dat_openPopup[dat_openPopup$trace == 1843, ]
+## --> still 50 (small data set) left, and some really do not seem to be
+## opened! Must be a log error
+# --> others should be closed!
+dat[31000:31019,]     # this one e.g.
+# --> Actually NOT! card gets flipped before! Again - log error!
+```
+Will probably just get rid of them!
+
+Think about if you want give warning messages about these deletions in the
+functions.
 
 # Reading list
 
diff --git a/code/02_preprocessing.R b/code/02_preprocessing.R
index 04151e3..a6438b6 100644
--- a/code/02_preprocessing.R
+++ b/code/02_preprocessing.R
@@ -30,6 +30,7 @@
 dat0 <- read.table("../data/rawdata_logfiles_small.csv", sep = ";",
                    header = TRUE)
 dat0$date <- as.POSIXct(dat0$date)  # create date object
+dat0$glossar <- ifelse(dat0$artwork == "glossar", 1, 0)
 
 #' # Remove irrelevant events
 
@@ -37,6 +38,7 @@ dat0$date <- as.POSIXct(dat0$date)  # create date object
 
 dat <- subset(dat0, !(dat0$event %in% c("Start Application",
                                         "Show Application")))
+rownames(dat) <- NULL
 
 #' # Close events
 
@@ -54,7 +56,7 @@ head(dat1[, c("event", "eventid")], 25)
 
 table(table(dat1$eventid))
 #   1     2     3     4     5     6     7     8    10    11
-#  73 78429  5156   842   222    66    18    14     3     1
+#  70 78435  5153   842   222    66    18    14     3     1 
 # --> compare to table(num_start)!
 
 # Find out how often "Transform stop" follows each other
@@ -80,18 +82,27 @@ id_rm_stop <- id_stop[diff(id_stop) == 1]
 dat1 <- dat1[-(id_rm_stop + 1), ]
 
 # transform to wide data format
-dat1$event <- ifelse(dat1$event == "Transform start", "start", "stop")
+dat1$time <- ifelse(dat1$event == "Transform start", "start", "stop")
 
 trans_wide <- reshape(dat1, direction = "wide",
-                      idvar = c("eventid", "artwork"),
-                      timevar = "event", drop = c("fileid", "popup", "card")
+                      idvar = c("eventid", "artwork", "glossar"),
+                      timevar = "time",
+                      drop = c("popup", "card", "event")
 )
-# --> when fileid is part of the reshape, it does not work correctly, since
-# we sometimes have a start - stop event that is recorded in two separate
-# log files
 # TODO: This runs for quite some time
 # --> Is this more efficient with tidyr::pivot_wider?
 
+# --> when fileid is part of the reshape, it does not work correctly, since
+# we sometimes have a start - stop event that is recorded in two separate
+# log files, BUT: after finding out, that `time_ms` changes for each log
+# file, I want to exclude those cases, so `fileid` has to be included!!!
+
+# check how often an eventid is associated with two fileids
+nrow(subset(trans_wide, trans_wide$fileid.start != trans_wide$fileid.stop))
+
+# exclude from data set ??
+# trans_wide <- subset(trans_wide, trans_wide$fileid.start != trans_wide$fileid.stop)
+
 # which(is.na(trans_wide$date.start))
 
 trans_wide$event <- "move"
@@ -116,38 +127,28 @@ trans_wide$popup <- NA
 dat_trans <- trans_wide[trans_wide$distance != 0 &
                         trans_wide$rotationDegree != 0 &
                         trans_wide$scaleSize != 1,
-                      c("event", "artwork", "trace", "date.start", "date.stop",
+                      c("fileid.start", "fileid.stop", "event", "artwork",
+                        "trace", "glossar", "date.start", "date.stop",
                         "time_ms.start", "time_ms.stop", "duration",
-                        "card", "popup",
-                        "x.start", "y.start", "x.stop", "y.stop",
-                        "distance", "scale.start", "scale.stop",
+                        "card", "popup", "x.start", "y.start", "x.stop",
+                        "y.stop", "distance", "scale.start", "scale.stop",
                         "scaleSize", "rotation.start", "rotation.stop",
                         "rotationDegree")]
+1 - nrow(dat_trans) / nrow(trans_wide)
 # removes almost 2/3 of the data (for small data set)
 
 rm(id_rm_stop, id_stop, trans_wide, num_start, num_stop)
 
 summary(dat_trans)
 
-# TODO: Ask Phillip what is wrong with `time_ms`
-# --> Hat er eine Erklärung dafür?
-
-#plot(time_ms.stop ~ time_ms.start, dat_trans, type = "b")
-plot(time_ms.stop ~ time_ms.start, dat_trans, 
-     col = rgb(red = 0, green = 0, blue = 0, alpha = 0.2))
-
-plot(date.stop ~ date.start, dat_trans[1:1000,], type = "b")
-
-
-
 
 #' # Close other events
 
 dat2 <- dat[!dat$event %in% c("Transform start", "Transform stop"), ]
-dat2$x <- NULL
-dat2$y <- NULL
-dat2$scale <- NULL
-dat2$rotation <- NULL
+# dat2$x <- NULL
+# dat2$y <- NULL
+# dat2$scale <- NULL
+# dat2$rotation <- NULL
 rownames(dat2) <- NULL
 
 # Create event ID for closing events
@@ -202,8 +203,6 @@ lut <- glossar_dict[glossar_dict$glossar_file %in% glossar_files, ]
 head(dat2[, c("artwork", "event", "popup", "trace")], 20)
 
 
-#df <- NULL
-
 for (file in lut$glossar_file) {
 
   artwork_list <- unlist(lut[lut$glossar_file == file, "artwork"])
@@ -231,16 +230,15 @@ for (file in lut$glossar_file) {
         (current_artwork %in% artwork_list) &
         dat2$popup[i] == file & (j-k == 0)) {
 
-      #df <- rbind(df, data.frame(file, current_artwork, i, j))
       dat2[i, "trace"] <- dat2[j, "trace"]
+      dat2[i, "artwork"] <- current_artwork
 
     }
   }
 }
-# dim(dat2[is.na(dat2$trace), ])
-# --> finds about half of the glossar entries for the small data set...
 
-# dat2[apply(df[, c("j", "i")], 1, c), c("artwork", "event", "popup", "trace")]
+# --> finds about half of the glossar entries for the small data set...
+table(is.na(dat2[dat2$glossar == 1, "trace"]))
 
 # REMEMBER: It can never bo 100% correct, since it is always possible that
 # several cards are open and that they link to the same glossar entry
@@ -251,45 +249,42 @@ lut[sapply(lut$artwork, length) == 1, "glossar_file"]
 # TODO: Fill in the ones that are associated with one artwork
 # --> Can't come up with something -- maybe ask AK???
 
-# TODO: How to check if one of the former "Show Infos" is correct
-# --> Can't come up with something -- maybe ask AK???
+single <- lut[sapply(lut$artwork, length) == 1, "glossar_file"]
+tmp <- subset(dat2, is.na(dat2$trace))$popup
+inside <- unique(tmp[tmp %in% lut[sapply(lut$artwork, length) == 1, "glossar_file"]])
+single_art <- unlist(lut[lut$glossar_file %in% inside, "artwork"])
+tmp_lut <- data.frame(glossar_file = sort(inside), artwork = single_art)
 
-# for (file in lut$glossar_file) {
-#
-#   artwork_list <- unlist(lut[lut$glossar_file == file, "artwork"])
-#
-#   for (i in seq_len(nrow(dat2))) {
-#
-#     if (dat2$event[i] == "Show Info") {
-#
-#       artworks <- NULL
-#       current_artwork <- dat2[i, "artwork"]
-#       j <- i
-#
-#     } else {
-#
-#       print(current_artwork)
-#       artworks <- c(artworks, dat2[i, "artwork"])
-#       print(artworks)
-#
-#     }
-#
-#     # if (dat2$artwork[i] == "glossar" &
-#     #     (current_artwork %in% artwork_list) &
-#     #     dat2$popup[i] == file) {
-#     #
-#     #   #df <- rbind(df, data.frame(file, current_artwork, i, j))
-#     #   dat2[i, "trace"] <- dat2[j, "trace"]
-#
-#     # }
-#   }
-# }
 
-# correct: 17940
-# incorrect: 17963
+dat2[dat2$glossar == 1, c("artwork", "popup", "glossar", "trace")]
+
+for (file in tmp_lut$glossar_file) {
+
+  for (i in seq_len(nrow(dat2))) {
+
+    if (dat2$event[i] == "Artwork/OpenCard" & dat2$artwork[i] %in% tmp_lut$artwork) {
+
+      current_artwork <- dat2[i, "artwork"]
+      j <- i
+
+    }
+
+    if (dat2$artwork[i] == "glossar" &
+        dat2$popup[i] == file) {
+
+      dat2[i, "trace"] <- dat2[j, "trace"]
+      dat2[i, "artwork"] <- current_artwork
+
+    }
+  }
+}
+
+
+dat2[14110:14130, ]
+
+# TODO: Integrate for loop into for loop above
 
 # TODO: "glossar" entry should be changed to the corresponding artwork
-# TODO: Add additional variable `glossar` with 0/1 or similar instead
 
 # TODO: For now: Exclude not matched glossar entries
 
@@ -304,12 +299,12 @@ rm(lut, current_artwork, file, glossar_dict, i, j, k, artwork_list,
 
 dat3 <- subset(df, df$event %in% c("Show Info", "Show Front"))
 
-dat3$event <- ifelse(dat3$event == "Show Info", "start", "stop")
+dat3$time <- ifelse(dat3$event == "Show Info", "start", "stop")
 
 flipCard_wide <- reshape(dat3, direction = "wide",
-                        idvar = c("trace", "artwork"),
-                        timevar = "event",
-                        drop = c("fileid", "popup", "card"))
+                        idvar = c("trace", "artwork", "glossar"),
+                        timevar = "time",
+                        drop = c("popup", "card"))
 flipCard_wide$event <- "flipCard"
 flipCard_wide$duration <- flipCard_wide$time_ms.stop -
   flipCard_wide$time_ms.start
@@ -329,14 +324,15 @@ flipCard_wide$rotation.start  <- NA
 flipCard_wide$rotation.stop   <- NA
 flipCard_wide$rotationDegree  <- NA
 
-dat_flipCard <- flipCard_wide[, c("event", "artwork", "trace",
-                                 "date.start", "date.stop",
-                                 "time_ms.start", "time_ms.stop",
-                                 "duration", "card", "popup",
-                                 "x.start", "y.start", "x.stop", "y.stop",
-                                 "distance", "scale.start", "scale.stop",
-                                 "scaleSize", "rotation.start",
-                                 "rotation.stop", "rotationDegree")]
+dat_flipCard <- flipCard_wide[, c("fileid.start", "fileid.stop", "event",
+                                  "artwork", "trace", "glossar",
+                                  "date.start", "date.stop",
+                                  "time_ms.start", "time_ms.stop",
+                                  "duration", "card", "popup", "x.start",
+                                  "y.start", "x.stop", "y.stop",
+                                  "distance", "scale.start", "scale.stop",
+                                  "scaleSize", "rotation.start",
+                                  "rotation.stop", "rotationDegree")]
 
 rm(flipCard_wide)
 
@@ -349,11 +345,11 @@ rownames(dat4) <- NULL
 num_start <- diff(c(0, which(dat4$event == "Artwork/CloseCard")))
 dat4$eventid <- rep(seq_along(num_start), num_start)
 
-dat4$event <- ifelse(dat4$event == "Artwork/OpenCard", "start", "stop")
+dat4$time <- ifelse(dat4$event == "Artwork/OpenCard", "start", "stop")
 
 openTopic_wide <- reshape(dat4, direction = "wide",
-                         idvar = c("eventid", "trace", "artwork", "card"),
-                         timevar = "event", drop = c("fileid", "popup"))
+                         idvar = c("eventid", "trace", "glossar", "artwork", "card"),
+                         timevar = "time", drop = "popup")
 openTopic_wide$event <- "openTopic"
 openTopic_wide$duration <- openTopic_wide$time_ms.stop -
   openTopic_wide$time_ms.start
@@ -372,47 +368,46 @@ openTopic_wide$rotation.start  <- NA
 openTopic_wide$rotation.stop   <- NA
 openTopic_wide$rotationDegree  <- NA
 
-dat_openTopic <- openTopic_wide[, c("event", "artwork", "trace",
-                                   "date.start", "date.stop",
-                                   "time_ms.start", "time_ms.stop",
-                                   "duration", "card", "popup", "x.start",
-                                   "y.start", "x.stop", "y.stop",
-                                   "distance", "scale.start", "scale.stop",
-                                   "scaleSize", "rotation.start",
-                                   "rotation.stop", "rotationDegree")]
+dat_openTopic <- openTopic_wide[, c("fileid.start", "fileid.stop", "event",
+                                    "artwork", "trace", "glossar",
+                                    "date.start", "date.stop",
+                                    "time_ms.start", "time_ms.stop",
+                                    "duration", "card", "popup", "x.start",
+                                    "y.start", "x.stop", "y.stop",
+                                    "distance", "scale.start",
+                                    "scale.stop", "scaleSize",
+                                    "rotation.start", "rotation.stop",
+                                    "rotationDegree")]
 # TODO: card should have a unique identifier for each artwork
 
 rm(openTopic_wide, num_start)
 
 #' ## close openPopup
 dat5 <- subset(df, df$event %in% c("ShowPopup", "HidePopup"))
-dat5 <- dat5[order(dat5$artwork, dat5$date), ]
+dat5 <- dat5[order(dat5$artwork, dat5$popup, dat5$date), ]
 rownames(dat5) <- NULL
 
 num_start <- diff(c(0, which(dat5$event == "HidePopup")))
-# last event is "ShowPopup"! Needs to be fixed 
-num_start <- c(num_start, 1)
-# TODO: Needs to be caught in a function
+# last event is "ShowPopup"! Needs to be fixed
+# num_start <- c(num_start, 1)
+# TODO: Needs to be caught in a function --> not anymore - still relevant???
 
 dat5$eventid <- rep(seq_along(num_start), num_start)
 
-dat5$event <- ifelse(dat5$event == "ShowPopup", "start", "stop")
+dat5$time <- ifelse(dat5$event == "ShowPopup", "start", "stop")
 
 openPopup_wide <- reshape(dat5, direction = "wide",
-                         idvar = c("eventid", "trace", "artwork", "popup"),
-                         timevar = "event", drop = c("fileid", "card"))
+                         idvar = c("eventid", "trace", "glossar", "artwork", "popup"),
+                         timevar = "time", drop = "card")
 # there is a pathological entry which gets deleted...
 # df[df$trace == 4595, ]
+# --> artwork 046 popup selene.xml gets opened twice
 
-# TODO: Some correct entries are not closed:
-df[df$trace == 1843, ]
-# WHY???
 
 openPopup_wide$event <- "openPopup"
 openPopup_wide$duration <- openPopup_wide$time_ms.stop -
   openPopup_wide$time_ms.start
 
-
 openPopup_wide$card            <- NA
 openPopup_wide$x.start         <- NA
 openPopup_wide$x.stop          <- NA
@@ -426,14 +421,16 @@ openPopup_wide$rotation.start  <- NA
 openPopup_wide$rotation.stop   <- NA
 openPopup_wide$rotationDegree  <- NA
 
-dat_openPopup <- openPopup_wide[, c("event", "artwork", "trace",
-                                   "date.start", "date.stop",
-                                   "time_ms.start", "time_ms.stop",
-                                   "duration", "card", "popup", "x.start",
-                                   "y.start", "x.stop", "y.stop",
-                                   "distance", "scale.start", "scale.stop",
-                                   "scaleSize", "rotation.start",
-                                   "rotation.stop", "rotationDegree")]
+dat_openPopup <- openPopup_wide[, c("fileid.start", "fileid.stop", "event",
+                                    "artwork", "trace", "glossar",
+                                    "date.start", "date.stop",
+                                    "time_ms.start", "time_ms.stop",
+                                    "duration", "card", "popup", "x.start",
+                                    "y.start", "x.stop", "y.stop",
+                                    "distance", "scale.start",
+                                    "scale.stop", "scaleSize",
+                                    "rotation.start", "rotation.stop",
+                                    "rotationDegree")]
 rm(num_start, openPopup_wide)
 
 
@@ -443,14 +440,14 @@ rm(num_start, openPopup_wide)
 # dat_all <- merge(dat_all, dat_openTopic, all = TRUE)
 # dat_all <- merge(dat_all, dat_openPopup, all = TRUE)
 # })
-# 
+#
 # # check
 # nrow(dat_all) == (nrow(dat_trans) + nrow(dat_flipCard) +
 #                   nrow(dat_openTopic) + nrow(dat_openPopup))
-# 
+#
 # dat_all <- dat_all[order(dat_all$date.start), ]
 # rownames(dat_all) <- NULL
-# 
+#
 
 # TODO: from here on NA... WHY??
 # dat_all[19426:19435, ]
@@ -460,10 +457,10 @@ rm(num_start, openPopup_wide)
 # dat_all2 <- dplyr::full_join(dat_trans, dat_flipCard)
 # dat_all2 <- dplyr::full_join(dat_all, dat_openTopic)
 # dat_all2 <- dplyr::full_join(dat_all, dat_openPopup)
-# 
+#
 # nrow(dat_all2) == (nrow(dat_trans) + nrow(dat_flipCard) +
 #                   nrow(dat_openTopic) + nrow(dat_openPopup))
-# 
+#
 # dat_all2 <- dat_all2[order(dat_all2$date.start), ]
 # rownames(dat_all2) <- NULL
 # TODO: --> same result - but faster. Need it?
@@ -479,8 +476,22 @@ nrow(dat_all) == (nrow(dat_trans) + nrow(dat_flipCard) +
                   nrow(dat_openTopic) + nrow(dat_openPopup))
 
 # remove all events that do not have a `date.start`
+dim(dat_all[is.na(dat_all$date.start), ])
 dat_all <- dat_all[!is.na(dat_all$date.start), ]
-# TODO: Find out how it can be that there is only a `date.stop`
+# There is only a `date.stop`, when event is not properly closed, see here:
+df[df$trace == 1843, ]
+dat_openPopup[dat_openPopup$trace == 1843, ]
+## --> still 50 (small data set) left, and some really do not seem to be
+## opened! Must be a log error
+# --> others should be closed!
+dat[31000:31019,]     # this one e.g.
+# --> Actually NOT! card gets flipped before! Again - log error!
+
+
+# Remove durations when event spans more than one log file, since they are
+# not interpretable
+dat_all[which(dat_all$fileid.start != dat_all$fileid.stop), "duration"] <- NA
+
 
 # sort by `start.date`
 dat_all <- dat_all[order(dat_all$date.start), ]
@@ -521,7 +532,8 @@ head(dat_all[, c("event", "artwork", "trace", "date.start", "timediff", "case")]
 
 dat_all$eventid <- seq_len(nrow(dat_all))
 
-dat_all <- dat_all[, c("eventid", "case", "trace", "event", "artwork",
+dat_all <- dat_all[, c("fileid.start", "fileid.stop", "eventid", "case",
+                       "trace", "glossar", "event", "artwork",
                        "date.start", "date.stop", "time_ms.start",
                        "time_ms.stop", "duration", "card", "popup",
                        "x.start", "y.start", "x.stop", "y.stop",
@@ -574,6 +586,7 @@ for (case in cases) {
     }
   }
 }
+
 # TODO: Get rid of the loops
 # --> This takes forever...
 
@@ -587,25 +600,20 @@ for (case in cases) {
 
 # put glossar events back in
 
-dat_all <- rbind(out, dat_all[dat_all$artwork == "glossar", ])
-dat_all <- dat_all[order(dat_all$date.start), ]
-rownames(dat_all) <- NULL
+#dat_all <- rbind(out, dat_all[dat_all$artwork == "glossar", ])
+out <- out[order(out$date.start), ]
+rownames(out) <- NULL
 
 # Make `trace` a consecutive number
-dat_all$trace <- as.numeric(as.factor(dat_all$trace))
-
-
-# TODO: How to handle duration < 0
-# --> Replace with NA for now...
-dat_all$duration <- ifelse(dat_all$duration < 0, NA, dat_all$duration)
+out$trace2 <- as.numeric(factor(out$trace, levels = unique(out$trace)))
 
+#head(out[, c("trace", "trace2")], 50)
 
 #' # Export data
 
-write.table(dat_all, "../data/event_logfiles.csv",
+write.table(out, "../data/event_logfiles.csv",
             sep = ";", quote = FALSE, row.names = FALSE)
 
-
 # Is `artwork` my case? Or `artwork` per day? Or `artwork` per some other
 # unit??? Maybe look at differences between timestamps separately for
 # `artwork`? And identify "new observational unit" this way?
@@ -621,6 +629,3 @@ write.table(dat_all, "../data/event_logfiles.csv",
 
 # TODO: Write function for closing events
 
-
-
-
diff --git a/code/01b_investigate.R b/code/zz_investigate.R
similarity index 96%
rename from code/01b_investigate.R
rename to code/zz_investigate.R
index 870a30d..3cbb897 100644
--- a/code/01b_investigate.R
+++ b/code/zz_investigate.R
@@ -237,3 +237,12 @@ counts <- table(as.Date(dat$date[dat$event %in% start_events]),
 lattice::barchart(counts, auto.key = TRUE)
 
 
+# TODO: Ask Phillip what is wrong with `time_ms`
+# --> Hat er eine Erklärung dafür?
+
+#plot(time_ms.stop ~ time_ms.start, dat_trans, type = "b")
+plot(time_ms.stop ~ time_ms.start, dat_trans, 
+     col = rgb(red = 0, green = 0, blue = 0, alpha = 0.2))
+
+plot(date.stop ~ date.start, dat_trans[1:1000,], type = "b")
+