Read-in datafiles
First, read in the individual subject files (saved automatically on the server as csv files).
tbl_all <- list.files(path = "./Ma_data/", pattern = "*.csv", full.names = T) %>%
map_df(~read_csv(.))
tbl_all <- data.frame(tbl_all)
#head(tbl_all,10)
Get a count of the number of subjects.
nrow(tbl_all %>% distinct(workerId,.keep_all = FALSE))
## [1] 63
Next, rename the catch trials to the same convention as the main trials and break apart the unmod_image column into database (the lab where the stims come from) and image (the name of the image file).
tbl_all$unmod_image[tbl_all$unmod_image == "catchAirplane-a"] <- "rensink_catchAirplane-a"
tbl_all$unmod_image[tbl_all$unmod_image == "catchBoat-a"] <- "rensink_catchBoat-a"
tbl_all$unmod_image[tbl_all$unmod_image == "catchCow-a"] <- "rensink_catchCow-a"
tbl_all <- tbl_all %>%
separate(unmod_image,into=c('database', 'image', NA), sep = "([\\_\\-])")
#head(tbl_all,10)
Let’s, for now, also assign the trials to bins based on the trial number. The 2 practice trials at the beginning and the 1 catch trial at the end will be labeled “filler”.
tbl_all$bin = "filler"
tbl_all[which(tbl_all$trial_number %in% c(3:8)), "bin"] = "block_1"
tbl_all[which(tbl_all$trial_number %in% c(9:14)), "bin"] = "block_2"
tbl_all[which(tbl_all$trial_number %in% c(15:20)), "bin"] = "block_3"
tbl_all[which(tbl_all$trial_number %in% c(21:26)), "bin"] = "block_4"
tbl_all[which(tbl_all$trial_number %in% c(27:32)), "bin"] = "block_5"
Get the total number of trials for each subject and the initial count for each image.
tbl_all_counts <- tbl_all %>%
group_by(workerId,image) %>%
filter(image!= "catchAirplane" & image!= "catchBoat" & image!= "catchCow") %>%
dplyr::summarize(counts = n()) %>%
spread(image,counts) %>%
mutate(sum = rowSums(.[-1], na.rm = TRUE))
#head(tbl_all_counts,10)
image_count_initial <- data.frame(image_count = colSums(tbl_all_counts[,2:70], na.rm = TRUE))
image_count_initial
## image_count
## 10504629 27
## 10810329 25
## 1191801 28
## 12115280 25
## 12178414 27
## 13141692 27
## 1383096 30
## 13873251 28
## 16527526 28
## 18169626 27
## 18345691 28
## 22020472 28
## 23024660 30
## 23199105 27
## 24383097 25
## 25107991 28
## 27857618 25
## 3099758 28
## 31236119 28
## 32289063 26
## 38466626 28
## 38546029 28
## 42429798 24
## 4247084 29
## 44993860 23
## 45525109 29
## 46475259 27
## 46635293 27
## 48384711 25
## 48486405 29
## 51537628 29
## 51856108 29
## 55174490 26
## 56835136 27
## 57861456 26
## 61118260 30
## 62096551 29
## 62224663 30
## 67862299 29
## 69128765 27
## 70687495 27
## 72488522 29
## 73637203 27
## 74173745 27
## 75081153 25
## 75958241 26
## 77345858 27
## 77574131 29
## 77793328 28
## 79191795 29
## 79222679 27
## 79241011 29
## 79573638 28
## 8197559 26
## 81993755 28
## 83536470 28
## 83691215 28
## 83785171 26
## 85741618 27
## 86520382 29
## 87983207 26
## 88767165 27
## 89354846 30
## 8974554 27
## 90405028 27
## 95091295 26
## 97475929 28
## 98156944 26
## 98265889 26
The data are loaded. Let’s move on and examine the quality of the data.
Analyze accuracy
In this chunk, every click for a given image is compared to the image difference hull. The process involves the addition of two arrays - the difference hull array and an array created by the script and the subject’s click. The difference hull array is composed of 0s and 1s, with 1s corresponding to the changing object. An equally sized array of all 0s is composed, with one 1 corresponding to the X,Y coordinates of the click. These two arrays are added together and the maximum value is queried. A maximum value of 2 indicates that the click occurred within the boundaries of the image difference hall (an accurate click). A values less than 2 indicates that the click occurred outside the boundaries of the image difference hall (an inaccurate click). In the new click_ACC column, 1s correspond to accurate clicks and 0s correspond to inaccurate clicks. This will analyze the accuracy for the 2 practice images, all main images, and the 1 catch image.
img_train <- list.files(path = "/Users/adambarnas/Box/Mudsplash/Boxes_Ma/", pattern = ".png", all.files = TRUE,full.names = TRUE,no.. = TRUE)
img_array <- readPNG(img_train)
img_list <- lapply(img_train, readPNG)
img_names <- row.names(image_count_initial)
img_names <- c("catchAirplane", "catchBoat", "catchCow", img_names)
names(img_list) = img_names
tbl_all$x[tbl_all$x == "0"] <- 1
tbl_all$y[tbl_all$y == "0"] <- 1
tbl_all$click_ACC= "filler"
for (i in 1:length(tbl_all$workerId)){
img <- data.frame(img_list[tbl_all$image[i]])
blank <- data.frame(array(c(0,0), dim = c(nrow(img),ncol(img))))
blank[tbl_all$y[i], tbl_all$x[i]] <- 1
combo <- img + blank
which(combo==2, arr.ind=TRUE)
if (max(combo, na.rm=TRUE) == 2){
tbl_all$click_ACC[i] = 1
} else {
tbl_all$click_ACC[i] = 0
}
}
Catch trials
Check the accuracy of the catch trial. As a reminder, the catch trial was a large, salient changing object. If a subject did not click on the changing object during the catch trial, their performance on the main trials is likely poor and will be excluded. This chunk will filter the data by accuracy for both inaccurate (bad) catch trials and accurate (good) catch trials and save new dataframes. This chunk will also provide the number and workerIds for inaccurate and accurate catch trial performance.
tbl_all_catch_acc <- tbl_all %>%
filter(image == "catchCow")
tbl_bad_catch_acc <- tbl_all_catch_acc %>%
filter(click_ACC == 0)
tbl_good_catch_acc <- tbl_all_catch_acc %>%
filter(click_ACC == 1)
tbl_bad_catch_acc <- tbl_all[(tbl_all$workerId %in% tbl_bad_catch_acc$workerId),]
nrow(tbl_bad_catch_acc %>% distinct(workerId,.keep_all = FALSE))
## [1] 1
tbl_good_catch_acc <- tbl_all[(tbl_all$workerId %in% tbl_good_catch_acc$workerId),]
nrow(tbl_good_catch_acc %>% distinct(workerId,.keep_all = FALSE))
## [1] 62
Main trials
Now, check the accuracy of the clicks for the main images. This chunk will compute the total number of inaccurate and accurate clicks for each subject.
tbl_good_catch_acc_all_main_acc <- tbl_good_catch_acc %>%
filter(image!= "catchAirplane" & image!= "catchBoat" & image!= "catchCow")
tbl_good_catch_acc_all_main_acc_counts <- tbl_good_catch_acc_all_main_acc %>%
group_by(workerId,click_ACC) %>%
dplyr::summarize(counts = n()) %>%
spread(click_ACC,counts) %>%
mutate(total = rowSums(.[2:3], na.rm = TRUE))
colnames(tbl_good_catch_acc_all_main_acc_counts) <- c("workerId", "inacc", "acc", "total")
Here, we can plot the overall accuracy of the main trial clicks for the group and for each individual subject. We can split the group by accuracy rate and plot “bad” and “good” subgroups. Subjects who clicked on the changing object 75% or more of the time are grouped as “good” and subjects who clicked on the changing object less than 75% are grouped as “bad”.
tbl_good_catch_acc_all_main_acc_rate <- (tbl_good_catch_acc_all_main_acc_counts$acc / tbl_good_catch_acc_all_main_acc_counts$total)
tbl_good_catch_acc_all_main_acc_rate <- cbind.data.frame(tbl_good_catch_acc_all_main_acc_counts[,1], tbl_good_catch_acc_all_main_acc_rate)
colnames(tbl_good_catch_acc_all_main_acc_rate) <- c("workerId", "acc_rate")
tbl_good_catch_acc_all_main_acc_rate[is.na(tbl_good_catch_acc_all_main_acc_rate)] <- 0
tbl_good_catch_acc_all_main_acc_rate$cat = "filler"
for (i in 1:length(tbl_good_catch_acc_all_main_acc_rate$workerId)){
if (tbl_good_catch_acc_all_main_acc_rate$acc_rate[i] >= 0.75){
tbl_good_catch_acc_all_main_acc_rate$cat[i] = "Good"
} else {
tbl_good_catch_acc_all_main_acc_rate$cat[i] = "Bad"
}
}
tbl_good_catch_acc_good_main_acc_rate <- tbl_good_catch_acc_all_main_acc_rate %>%
filter(acc_rate >= 0.75)
tbl_good_catch_acc_bad_main_acc_rate <- tbl_good_catch_acc_all_main_acc_rate %>%
filter(acc_rate < 0.75)
tbl_good_catch_acc_all_main_acc_rate %>%
ggbarplot(y = "acc_rate", ylab = "Accuracy", fill = "#f7a800", color = "#f7a800", add = "mean_se", ylim = c(0, 1), xlab = "Group", width = 0.5, label = TRUE, lab.nb.digits = 2, lab.vjust = -1.6, title = "Main Trial Accuracy for All Subjects")

tbl_good_catch_acc_all_main_acc_rate %>%
ggbarplot(x = "workerId", y = "acc_rate", ylab = "Accuracy", fill = "#f7a800", color = "#f7a800", ylim = c(0, 1), title = "Main Trial Accuracy for Individual Subjects", font.xtickslab = 8, sort.val = c("asc")) + rotate_x_text() + geom_hline(yintercept = .75, linetype = 2)

tbl_good_catch_acc_all_main_acc_rate %>%
ggbarplot(x = "cat", y = "acc_rate", ylab = "Accuracy", xlab = "Accuracy Group", add = "mean_se", fill = "#f7a800", color = "#f7a800", ylim = c(0, 1), label = TRUE, lab.nb.digits = 2, lab.vjust = c(-2.3, -0.8), title = "Main Trial Accuracy for Bad and Good Subjects", sort.val = c("asc"))

This dataframe consists of subjects with good catch trial accuracy and good main trial accuracy (again, greater than 75%).
tbl_good_catch_acc_good_main_acc <- tbl_good_catch_acc_all_main_acc[(tbl_good_catch_acc_all_main_acc$workerId %in% tbl_good_catch_acc_good_main_acc_rate$workerId),]
nrow(tbl_good_catch_acc_good_main_acc %>% distinct(workerId,.keep_all = FALSE))
## [1] 38
Remove inaccurate trials from the subjects with good main accuracy.
tbl_good_catch_acc_good_main_acc_inacc_trials_removed <- tbl_good_catch_acc_good_main_acc %>%
filter(click_ACC == 1)
Remove outlier trials
Next, we can remove outlier RTs that are more than 3 SDs away from the mean.
Let’s get the number of trials. This is the initial number of trials.
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed %>%
group_by(workerId,image) %>%
dplyr::summarize(counts = n()) %>%
spread(image,counts) %>%
mutate(sum = rowSums(.[-1], na.rm = TRUE))
#head(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts,10)
Before the data are trimmed, let’s generate histograms of all RTs and the mean RT of each subject
tbl_good_catch_acc_good_main_acc_inacc_trials_removed$rt_s = tbl_good_catch_acc_good_main_acc_inacc_trials_removed$rt/1000
tbl_good_catch_acc_good_main_acc_inacc_trials_removed %>%
gghistogram(x = "rt_s", fill = "#f7a800", rug = TRUE, bins = 60, xlim = c(0,60), ylim = c(0,400), xlab = ("Detection RT (sec)"), title = "All RTs")

tbl_good_catch_acc_good_main_acc_inacc_trials_removed_mean_subj_RT <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed %>%
group_by(workerId) %>%
dplyr::summarize(mean_rt = mean(rt_s, na.rm=TRUE))
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_mean_subj_RT %>%
gghistogram(x = "mean_rt", fill = "#f7a800", rug = TRUE, bins = 20, xlim = c(0,20), ylim = c(0,8), xlab = ("Mean Detection RT (sec)"), title = "Subject Mean RT")

Trial timer maxed out at 60 sec. Any RTs recorded as 60 sec should be discarded.
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed %>%
filter(rt < 60000)
Next, data are inspected for RT outliers. Two additional columns are added to the data table. First, an “outliers” column is added that labels an RT as an outlier or not (0 = not an outlier, 1 = an outlier less than 3 SDs, 2 = an outlier greater than 3 SDs). Second, a “removed_RT” column is added that contains non-outlier RTs.
Note: code can be changed to allow for replacement of outliers with the cutoff values.
correct.trials <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed[tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed$click_ACC == "1",]
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed <- ddply(correct.trials, .(workerId), function(x){
m <- mean(x$rt)
s <- sd(x$rt)
upper <- m + 3*s #change 3 with another number to increase or decrease cutoff criteria
lower <- m - 3*s #change 3 with another number to increase or decrease cutoff criteria
x$outliers <- 0
x$outliers[x$rt > upper] <- 2
x$outliers[x$rt < lower] <- 1
x$removed_RT <- x$rt
x$removed_RT[x$rt > upper]<- NA #change NA with upper to replace an outlier with the upper cutoff
x$removed_RT[x$rt < lower]<- NA #change NA with lower to replace an outlier with the lower cutoff
x
})
#head(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed,10)
Next, let’s completely toss out the outlier trials (labeled as NA).
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed[!is.na(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed$removed_RT),]
#head(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed,10)
Let’s get the number of trials. This is the number of trials that “survive” the data trimming.
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed_counts <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed %>%
group_by(workerId,image) %>%
dplyr::summarize(counts = n()) %>%
spread(image,counts) %>%
mutate(sum = rowSums(.[-1], na.rm = TRUE))
#head(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed_counts,10)
Here are new histograms of all RTs and the mean RT of each subject.
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed %>%
gghistogram(x = "rt_s", fill = "#f7a800", rug = TRUE, bins = 60, xlim = c(0,60), ylim = c(0,400), xlab = ("Detection RT (sec)"), title = "All RTs")

tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed_mean_subj_RT <- tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed %>%
group_by(workerId) %>%
dplyr::summarize(mean_rt = mean(rt_s, na.rm=TRUE))
tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed_mean_subj_RT %>%
gghistogram(x = "mean_rt", fill = "#f7a800", rug = TRUE, bins = 20, xlim = c(0,20), ylim = c(0,8), xlab = ("Mean Detection RT (sec)"), title = "Subject Mean RT")

What is the percentage of outlier RTs that were removed overall?
tbl_rts_3SD_removed_count <- data.frame(total_removed = tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts$sum - tbl_good_catch_acc_good_main_acc_inacc_trials_removed_timeout_trials_removed_rts_3SD_trimmed_rts_3SD_removed_counts$sum)
per_RTs_removed <- (sum(tbl_rts_3SD_removed_count) / sum(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts$sum)) * 100
per_RTs_removed
## [1] 2.544031
What is the percentage of outlier RTs that were removed per subject? This is easy to visualize in a plot.
tbl_per_rts_3SD_removed_by_subj <- data.frame((tbl_rts_3SD_removed_count / tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts$sum) * 100)
tbl_per_rts_3SD_removed_by_subj <- cbind.data.frame(tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts[1],tbl_rts_3SD_removed_count,tbl_good_catch_acc_good_main_acc_inacc_trials_removed_counts$sum,tbl_per_rts_3SD_removed_by_subj)
colnames(tbl_per_rts_3SD_removed_by_subj) <- c("workerId", "outlier_RTs", "total_RTs", "percent_excluded")
#head(tbl_per_rts_3SD_removed_by_subj,10)
tbl_per_rts_3SD_removed_by_subj %>%
ggbarplot(x = "workerId", y = "percent_excluded", ylab = "% RTs excluded", fill = "#f7a800", font.tickslab = 8, sort.val = c("asc")) + rotate_x_text()
