By default, the quiz summary shows statistics for all sections including the quiz average score, high score, low score, standard deviation (how far the values are spread across the entire score range), and average time of quiz completion [1].
To view quiz statistics for a section, click the Section Filter drop-down menu [2]. To access additional survey results, generate a Student/Item Analysis report [3].
In the summary graph, the x-axis indicates the quiz scored percentages [4], and the y-axis indicates the number of students who received each percentage [5].
If a student had multiple assignment attempts, you can view past attempts in SpeedGrader. Quiz stats will only display the kept score for the student (highest score or latest score). To view the score setting for multiple attempts, edit your quiz and view the multiple attempts settings option. If necessary, you can give your students an extra attempt.