This directory contains the raw data of four online experiments through the Amazon Mechanical Turk, and R code for data analysis. We provide the experiment results of the formal study into the folder: data. You can download the whole dataset and run the R code for data analysis. For each file in the data folder, the file is named as "TaskName-UserId.csv", including four tasks: counting_task, highlighting_task, context_task, constancy_task. As for each task, the recorded data includes different variables, that is: 1. userName: indicated by a temporary user mTurk Id. 2. fileId: the file id of the scatterplot, from 0 to 11, -1 indicates engagement check trial. 3. conditionId: the condition id of each trial, from 0 to 3, -1 indicates engagement check trial. 4. clusterNum: the cluster number of the scatterplot. 5. clusterId: the cluster id of the actually highlighted class. 6. selectId: the cluster id of the target selected class, not used. 6. userResult: user answer of the given trial for the task 7. totalTime: the consuming time of the given trial for the task 8. correctAns: the correct answer of the given trial for the task Now it's ready to analysis the experiment data.