Assessments¶
NOTE: Any time you edit or add an infoAssessment.json
file on a local copy of PrairieLearn, you need to click the “Load from disk” button in the header so that the local PrairieLearn server reloads the changes.
Overview¶
Each assessment is a single directory in the assessments
folder or any subfolder. Assessments may be nested in subdirectories of the assessments
folder. The assessment directory must contain a single file called infoAssessment.json
that describes the assessment and looks like:
{
"uuid": "cef0cbf3-6458-4f13-a418-ee4d7e7505dd",
"type": "Exam",
"title": "Coordinates and Vectors",
"set": "Quiz",
"module": "Linear algebra review",
"number": "2",
"allowAccess": [],
"zones": [],
"comment": "You can add comments to JSON files using this property."
}
The assessment ID is the full path relative to assessments
.
Assessment naming¶
Assessments are organized into sets
(e.g., Homework
, Quiz
, Exam
) and within each set the assessment has a number
. Additionally, each assessment has a title
. Depending on the context, assessments are referred to by either a short name or a long name. The format of these is:
- Short name =
Set Number
(e.g.,Quiz 2
in the above example).
- Long name =
Set Number: Title
(e.g.,Quiz 2: Coordinates and Vectors
above).
You can select a set from the list of standardized assessment sets or create your own.
Assessment modules¶
Instructors may want to group their assessments by course modules (topics, sections or chapters in a course). When using "groupAssessmentsBy" : "Module"
in infoCourseInstance.json
, instructors can assign an assessment to a specific module by setting the module
property in infoAssessment.json
, as illustrated in the example above. If the property module
is omitted, by default the assessment will have "module" : "Default"
.
For more information about how to create your own assessment modules, see Course configuration.
Assessment types¶
Each assessment has a type
set to either Homework
or Exam
, as listed below.
Homework |
Exam |
|
---|---|---|
General purpose | Formative assessments, practice | Summative assessments, measure learning |
Randomized questions | Multiple variants (if question supports them) | Each student gets a single variant |
Number of attempts | Unlimited attempts | Limited attempts, possibly with decreasing points |
Gamification | Rewards repeated correct answers | Incentivizes a correct answer as early as possible |
Question order | Fixed order by default | Shuffled order within zones by default |
Time limits | Not supported | Supported |
Passwords | Not supported | Supported |
Multiple instances | Not supported | Supported |
Assessment updates | Updated if assessment changes | Assessment is fixed on creation |
Closing assessments | Assessments remain open | By default, idle assessments are closed after 6 hours |
Honor pledge | Not supported | Enabled by default |
Real-time grading | Always enabled | Can be disabled |
Changing question-order randomization¶
To make Homework
assessments randomize the question order for each student, set the "shuffleQuestions": true
option in the infoAssessment.json
file. This will use a unique-per-course number for each question, so that all students will still get the same question numbers (like #427), but they will not be in order. This makes it easy for students to discuss questions with course staff; they can say “I don't know how to do #427” and everyone will be seeing the same question #427. The main advantage of randomizing question order on Homeworks is to enable data collection on question difficulty and student behavior that is independent of the order in which questions are listed on the assessment.
On Exam
assessments, questions are randomized by default, but this can be disabled by setting "shuffleQuestions": false
in the infoAssessment.json
file.
Question specification¶
An assessment is broken down in to a list of zones, like this:
"zones": [
{
"title": "Easy questions",
"comment": "These are new questions created for this exam",
"questions": [
{"id": "anEasyQ", "autoPoints": [10, 5, 3, 1, 0.5, 0.25]},
{"id": "aSlightlyHarderQ", "autoPoints": [10, 9, 7, 5]}
]
},
{
"title": "Hard questions",
"comment": "These are new questions created for this exam",
"questions": [
{"id": "hardQV1", "autoPoints": 10},
{"id": "reallyHardQ", "autoPoints": [10, 10, 10]},
{
"numberChoose": 1,
"autoPoints": 5,
"alternatives": [
{"id": "FirstAltQ", "autoPoints": 10},
{"id": "SecondAltQ"}
]
}
]
},
{
"title": "Manually graded questions",
"comment": "These are questions that include manual grading components",
"questions": [
{"id": "essayQ", "manualPoints": 10},
{"id": "autoPlusManualQ", "autoPoints": [10, 7, 5], "manualPoints": 15},
]
}
],
- Each zone appears in the given order in the assessment. Zone titles are optional and are displayed to the student if present.
- Within each zone the question order is randomized based on the assessment type and the
shuffleQuestions
option.
- An assessment question can be specified by either a single
id
or by a list of alternatives, in which case one or more of these alternatives is chosen at random. Once the questionid
is determined, then a random variant of that question is selected. Question alternatives inherit the points of their parent group, if specified.
- If a zone has
maxPoints
, then, of the points that are awarded for answering questions in this zone, at mostmaxPoints
will count toward the total points.
- If a zone has
bestQuestions
, then, of the questions in this zone, onlybestQuestions
with the highest number of awarded points will count toward the total points.
Question points for Homework
assessments¶
Assessments with "type": "Homework"
are designed to allow students to repeatedly practice different variants of questions (that is, different random values in the question) until they achieve mastery. The assumption here is that any student should be able to receive full points for a homework question if they work long enough on it. See Question scoring details for Homework
assessments for details on the exact scoring algorithm.
Each question is assigned a set number of auto points (points that are automatically assigned by an internal or external grader) and manual points (points that are assigned manually by a human grader).
Auto-grading points are set using the autoPoints
value, which must be a single number and which corresponds to the initial value of a correct attempt. For example, if we have "autoPoints": 3
then a correct answer is worth 3 points, while a 50%-correct answer is worth 1.5 points.
If a student answers a question incorrectly, a new question variant is generated with new random numbers and the student can try again. There is no penalty for incorrect answers and students can try as many times as they like. Also see the triesPerVariant
option in Limiting the number of attempts for each question.
To encourage students to solve the same question correctly more than once (to emphasize mastery), a question can have maxAutoPoints
set to a value that is more than autoPoints
. In this case a student can get credit for multiple correct solutions, each for a different randomized variant, until reaching maxAutoPoints
. For example, if we have "autoPoints": 3
and "maxAutoPoints": 9
then the student could solve three different variants of the question correctly and receive 3 points for each of them. After this the student can continue to solve the question for practice but they will not receive any more points for it. If maxAutoPoints
is not specified then the question acts as if maxAutoPoints
is equal to autoPoints
. The use of maxAutoPoints
means that the question has a total value of maxAutoPoints
points, so in the previous example this is effectively a 9-point question (from maxAutoPoints
) even though autoPoints
is set to 3. To receive full points for the question the student will have to answer it correctly more than once.
By default, when using maxAutoPoints
, PrairieLearn provides an incentive for students to answer a specific question correctly multiple times in a row. This is done by increasing the value of each submission for every consecutive correct answer, while setting it back to the original value if the answer is incorrect or partially correct. So, for example, if autoPoints
is 3 and maxAutoPoints
is 30, then the first correct answer is worth 3 points. If the next submission is also fully correct, it will be worth 6 points; a following answer is worth 9 points if correct — for a total of 3+6+9=18 points earned; and so on. If any answer is incorrect or partially correct, the value earned for a new correctly-solved variant is reset to 3 points. To disable this behavior and keep the question value at a constant value of 3, set "constantQuestionValue": true
in the assessment settings, like this:
"constantQuestionValue": true,
"zones": [
{
"questions": [ ... ]
},
...
],
When using maxAutoPoints
, the number of correct answers needed to obtain the full points available for a question can vary depending on how many consecutive correct answers the student is able to submit. If we use "constantQuestionValue": true
then the question value never changes and so the number of correct answers needed is just maxAutoPoints / autoPoints
. However, in the default case when constantQuestionValue
is false, repeated correct answers will allow a student to reach the maxAutoPoints
more quickly. For example, with autoPoints
of 3 and maxAutoPoints
of 30, a student who answers the question correctly just 4 times in a row will receive the full 3+6+9+12=30 points. This means that a student who has achieved mastery can quickly complete the question. In contrast, a student who is struggling with the question may have to answer it correctly up to 30/3=10 times if they make repeated mistakes along the way to keep resetting the question value back to 3.
Manual grading points are set using the manualPoints
value. It is acceptable to use only one of autoPoints
or manualPoints
, in which case the other part of the points will be assigned a value of 0. Note that manual points are only applied to a question once, regardless of the number of submissions or variants the student answers.
A question may also set a value to points
instead of autoPoints
and manualPoints
. If this option is used, questions with a gradingMethod
set to Manual
will be assigned only manual points, while questions with other grading methods will be assigned only auto points. To avoid ambiguity, it is an error to use both points
and autoPoints
, or points
and manualPoints
, in the same question. If points
is used, then maxPoints
should be used instead of maxAutoPoints
.
Question points for Exam
assessments¶
Assessments with "type": "Exam"
are designed to test students' knowledge of course material. Students can retry questions for reduced points, so long as allowRealTimeGrading
is true (the default). See Question scoring details for Exam
assessments for details on the exact scoring algorithm.
Each question is assigned a set number of auto points (points that are automatically assigned by an internal or external grader) and manual points (points that are assigned manually by a human grader).
Exam questions only ever generate a single random variant of the question, but students may be able to make multiple attempts to answer the question (assuming that the default of allowRealTimeGrading
is used so that students can know whether their answers are incorrect and need to be reattempted). For each question, auto-grading points are set using the autoPoints
value, which is a list of values like [10, 7, 5]. This would mean that a correct answer on the first attempt is worth 10 points, a correct answer on the second attempt is worth 7 points, and so on. If autoPoints
is set to a single value rather than a list then only a single attempt is allowed for that number of points.
If a student receives partial credit for an answer then they receive correspondingly reduced points. For example, with [10, 7, 5] autoPoints
, a 50%-correct submission on the first attempt would be worth 5 points. The exact details of how points are awarded are described in Question scoring details for Exam
assessments. The principles of this scoring system are that students should be incentivized to answer questions correctly as soon as possible, and that students should never lose points by attempting a question again.
Manual grading points are set using the manualPoints
value. It is acceptable to use only one of autoPoints
or manualPoints
, in which case the other part of the points will be assigned a value of 0.
A question may also set a value to points
instead of autoPoints
and manualPoints
. If this option is used, questions with a gradingMethod
set to Manual
will be assigned only manual points, while questions with other grading methods will be assigned only auto points. To avoid ambiguity, it is an error to use both points
and autoPoints
, or points
and manualPoints
, in the same question. If points
is used, then maxPoints
should be used instead of maxAutoPoints
.
Question scoring details for Homework
assessments¶
This section describes in detail how repeated attempts are scored for Homework
questions, assuming that the question has autoPoints
. See Question points for Homework
assessments for a high-level overview. Scoring for manualPoints
is handled separately.
The two important question configuration settings are:
autoPoints
is the number of points that the student receives for a submission that is fully correct.maxAutoPoints
is the maximum number of points that the student can receive for a question, regardless of how many times they answer it correctly.
The basic idea is that students should receive autoPoints
each time they solve the question successfully, up to a maximum of maxAutoPoints
. When partial credit is awarded, a student receives partial points for the question, but only if they are getting closer to a correct answer. For example, if a student repeatedly answers a question with 50% correct answers then they will receive 50% points for the first such answer, but they will not be able to build up points to reach maxAutoPoints
. They will need to answer the question 100% correctly to be able to advance their points past the 50% mark.
The exact details of how PrairieLearn awards points are as follows. First, a number of variables are computed internally by PrairieLearn as the student answers the question:
- Submission percentage score is the score (between 0% and 100%) that the student receives for any given submission attempt, as evaluated by the question grading specification.
- Best current score is the highest submission percentage score the student has received so far. If the student has already achieved 100% for a submission at least once, it is the highest submission percentage score the student has received since last achieving 100% for a submission. This is initialized to zero.
- Question value is the current maximum number of points that the question is worth. This starts at
autoPoints
and increases byautoPoints
for each consecutive correct submission. This is initialized toautoPoints
. - Question points is the total number of points earned by the student for the question. This will never decrease. This is initialized to zero.
When a student submits an answer to a question, the submission is first checked for validity. For example, the pl-number-input
element considers a non-numeric input to be invalid. If the submission is valid then it is next determined whether it should be graded. A submission is only graded if explicitly requested by the student using the "Save & Grade" button, or if it is the last submission when the assessment is closed.
For each graded answer submission made by a student, the scoring algorithm is as follows:
- If the
submission percentage score
is more thanbest current score
, add(submission percentage score - best current score) / 100 * question value
toquestion points
, cappingquestion points
atmaxAutoPoints
. - If the
submission percentage score
is 100%, then resetbest current score
to zero. Otherwise, if thesubmission percentage score
is more thanbest current score
, then setbest current score
tosubmission percentage score
. - If the
submission percentage score
is 100% andconstantQuestionValue
is not set to true, then increasequestion value
byautoPoints
. Otherwise setquestion value
toautoPoints
.
As an example, suppose a student makes nine submissions of varying degrees of correctness to a question. Assume the question has autoPoints
set to 4 and maxAutoPoints
set to 16. The student's submissions are as follows:
Submission number | Submission perc. score | Best current score | Question value | Question points | Comment |
---|---|---|---|---|---|
Init | - | 0 | 4 | 0 | Initial values |
1 | 50% | 50% | 4 | 2 | (50% - 0%) * 4 = 2 points awarded |
2 | 80% | 80% | 4 | 3.2 | (80% - 50%) * 4 = 1.2 points awarded |
3 | 20% | 80% | 4 | 3.2 | No improvement in score, so no points awarded or deducted |
4 | 100% | 0% | 8 | 4 | (100% - 80%) * 4 = 0.8 points awarded, best current score reset to 0%, question value increased to 8 |
5 | 50% | 50% | 4 | 8 | (50% - 0%) * 8 = 4 points awarded, question value reset to 4 |
6 | 0% | 50% | 4 | 8 | No improvement in score, so no points awarded or deducted |
7 | 90% | 90% | 4 | 9.6 | (90% - 50%) * 4 = 1.6 points awarded or deducted |
8 | 100% | 0% | 8 | 10 | (100% - 90%) * 4 = 0.4 points awarded, best current score reset to 0%, question value increased to 8 |
9 | 100% | 0% | 12 | 16 | 100% * 8 = 8 points awarded but points are capped by maxAutoPoints of 16, best current score reset to 0%, question value increased to 12 |
After the nine submissions above the student has achieved maximum points for the question. They can continue to answer the question for additional practice but they cannot earn any more points for it.
Question scoring details for Exam
assessments¶
This section describes in detail how repeated attempts are scored for Exam
questions, assuming that the question has autoPoints
set to a list of values. See Question points for Exam
assessments for a high-level overview. Scoring for manualPoints
is handled separately.
The important question configuration setting is:
autoPoints
is a list of points, with then
-th entry being the number of points that a student receives for a fully correct submission on then
-th attempt at the question. IfautoPoints
is set to a single value rather than a list then only a single attempt is allowed.
The basic idea is that autoPoints
is set to a decreasing sequence of points, such as [10, 7, 5, 2]
. In this case, a correct answer on the first attempt is worth 10 points, a correct answer on the second attempt is worth 7 points, and so on. If the student does not answer the question correctly after four attempts, they will receive 0 points for the question and cannot attempt it again.
The details of how scoring works are made more complex by the fact that a student may receive partial credit for any given submission attempt. PrairieLearn uses a scoring system that has four key properties, assuming that autoPoints
is a list of decreasing values:
- A student can never lose points by attempting a question again.
- If a student submits an answer with a higher score than their previous best answer, they will always receive some additional points for it.
- Taking more attempts to answer correctly will always be worth less points than answering in fewer attempts, so students are always incentivized to answer questions correctly as soon as possible.
- The total number of submission attempts that a student can make is limited by the number of entries in
autoPoints
.
The exact details of how PrairieLearn awards points are as follows. First, a number of variables are computed internally by PrairieLearn as the student answers the question:
- Submission percentage score is the score (between 0% and 100%) that the student receives for any given submission attempt, as evaluated by the question grading specification.
- Best current score is the highest submission percentage score the student has received so far. This is initialized to zero.
- Question value is the current maximum number of points that the question is worth. This is equal to
autoPoints[n]
for then
-th attempt at the question. - Question points is the total number of points earned by the student for the question. This will never decrease. This is initialized to zero.
When a student submits an answer to a question, the submission is first checked for validity. For example, the pl-number-input
element considers a non-numeric input to be invalid. If the submission is valid then it is next determined whether it should be graded. A submission is only graded if explicitly requested by the student using the "Save & Grade" button, or if it is the last submission when the assessment is closed.
For the n
-th graded answer submission made by a student, the scoring algorithm is as follows:
- Set the
question value
toautoPoints[n]
. - If the
submission percentage score
is more thanbest current score
, add(submission percentage score - best current score) / 100 * question value
toquestion points
. - If the
submission percentage score
is more thanbest current score
, then setbest current score
tosubmission percentage score
. - If the
submission percentage score
is 100% and there are no manual points, orn
is the last attempt, then prohibit further submissions to the question.
As an example, suppose a student makes 4 submissions of varying degrees of correctness to a question which has autoPoints
set to [10, 7, 5, 2]
. The student's submissions are as follows:
Submission number | Submission perc. score | Best current score | Question value | Question points | Comment |
---|---|---|---|---|---|
Init | - | 0 | - | 0 | Initial values |
1 | 50% | 50% | 10 | 5 | (50% - 0%) * 10 = 5 points awarded |
2 | 20% | 50% | 7 | 5 | No improvement in score, so no points awarded or deducted |
3 | 80% | 80% | 5 | 6.5 | (80% - 50%) * 5 = 1.5 points awarded |
4 | 70% | 80% | 2 | 6.5 | No improvement in score, so no points awarded or deducted |
After the four submissions above the student has achieved 6.5 points for the question, for an overall score of 65% (6.5/10). They can no longer make submission attempts to the question.
Assessment and question instances and resetting assessments¶
PrairieLearn distinguishes between assessments and assessment instances. An assessment is determined by the code in an assessments
directory, and is something like "Midterm 1". Given an assessment, PrairieLearn needs to generate the random set of questions and question variants for each student, and it is this selection that is the assessment instance for the student. There is only one copy of each assessment, but every student has their own assessment instance. The rules for updating assessment instances differ between Homework
and Exam
assessments.
Exam
assessment updates: Exam assessment instances are generated when the student starts the exam, and they are never automatically deleted, regenerated, or updated, even when the original assessment is changed in some way. This is a safety mechanism to avoid having students' assessments changed during an exam. However, if you want to force the regeneration of assessment instances then you can do so by deleting assessment instances in the "Students" tab. While writing an assessment you might need to do this many times. Once an assessment is live, you should of course be very careful about doing this (basically, don't do it on a production server once an assessment is underway).
Homework
assessment updates: New questions added to Homeworks will be automatically integrated into student homeworks currently in progress. Updates to maxPoints
or maxBonusPoints
will take effect the next time a student grades a question. A student's "points" and "percentage score" will never decrease.
Assessment points¶
A student's percentage score will be determined by the number of points they have obtained, divided by the value of maxPoints
for the assessment (subject to the rules associated to credit
in assessment access rules).
{
"uuid": "cef0cbf3-6458-4f13-a418-ee4d7e7505dd",
"maxPoints": 50,
"maxBonusPoints": 5,
...
}
In the assessment configuration, the maxPoints
determines the number of points a student is required to obtain to get a score of 100%. The percentage score will thus be computed based on the points the student obtained divided by the value of maxPoints
. If not provided, maxPoints
is computed based on the maximum number of points that can be obtained from all questions in all zones.
By default, once a student obtains enough points to reach the value of maxPoints
, any further points do not affect the assessment score. However, if a value is set for maxBonusPoints
and credit
is set to 100, the student can obtain additional points, up to a total of maxPoints + maxBonusPoints
. The percentage is still based on maxPoints
, so the use of maxBonusPoints
allows students to obtain a percentage above 100%, either by completing additional questions, or by receiving additional bonus points in manual grading. If maxBonusPoints
is set, but maxPoints
is not provided, then maxPoints
will be computed by subtracting maxBonusPoints
from the maximum number of points in all questions.
The choice of using maxBonusPoints
or a credit
value above 100 is based on instructor's choice. Additional points based on maxBonusPoints
are intended to be credited based on extra work, while credit
above 100 is to be awarded for early completion. It is possible to combine them, and use them together in the same assessment. If maxBonusPoints
is set while the credit
is above 100, then the percentage is based on both maxBonusPoints
and credit
(see credit
for details).
Multiple-instance versus single-instance assessments¶
By default all assessments are single instance, meaning that each student has exactly one instance of the assessment that they can complete, and once they have completed that assessment instance then they cannot do the assessment again. This is the expected behavior for homeworks, quizzes, exams, etc.
For practice exams it is often desirable to make a multiple instance assessment by setting the option "multipleInstance": true
. This will allow students to create new assessment instances and try the whole assessment repeatedly.
Enabling group work for collaborative assessments¶
By default, assessment instances are tied to only one user. By setting groupWork: true
, multiple students will be able to work on the same assessment instance.
Information about the group configuration can be set in the infoAssessment.json
file. For example:
{
"groupWork": true,
"groupMaxSize": 6,
"groupMinSize": 2,
"studentGroupCreate": true,
"studentGroupJoin": true,
"studentGroupLeave": true
}
Attribute | Type | Default | Description |
---|---|---|---|
groupWork |
boolean | false | Enable the group work for the assessment. |
groupMaxSize |
integer | - | The maximum size of a group (default: no minimum). |
groupMinSize |
integer | - | The minimum size of a group (default: no maximum). |
studentGroupCreate |
boolean | false | Allow students to create groups. |
studentGroupJoin |
boolean | false | Allow students to join other groups by join code. |
studentGroupLeave |
boolean | false | Allow students to leave groups. |
Please notice: changing an assessment from group -> individual or vice versa after students have started working on it will cause student work to be lost.
Instructor options for groupWork¶
Underneath the "Groups" tab in an assessment, instructors have three ways of assigning students to different groups:
- Uploading a CSV file in the following format:
groupName,UID
groupA,one@example.com
groupA,two@example.com
groupB,three@example.com
groupB,four@example.com
-
Automatically assigning students, either to fill out existing groups or to make entirely new ones.
-
Copying the group assignments from another assessment.
A copy of the current group assignments can be saved from the "Downloads" tab, under <assessment>_group_configs.csv
Student options for groupWork¶
If an instructor does not assign a student to a group, the student will need to join one before opening their assessment instance. They can either create a new one or join an existing group via a join code, which they can get from another classmate.
When calculating a student's grade for a group assessment, PrairieLearn will always use the score of their group's assessment instance.
Note: Students cannot see each other's edits in real-time, although this is planned for a future version of PrairieLearn.
Students are able to see their groupmates' UIDs, which can become a point of contact to communicate with each other outside of PrairieLearn. They are also able to leave their group to join a different one.
Enabling custom group roles¶
By default, students working in a collaborative group assessments can view and submit every question. However, instructors can define custom group roles, which can be assigned different permissions to facilitate role-based teamwork. Assessments can be configured to allow or restrict some operations to students with specific roles, such as:
- Submitting specific questions
- Viewing specific questions
- Assigning group roles for other students
Although in most cases each student is expected to take one role, students are allowed to take on multiple roles in some narrow scenarios, such as when users leave and join groups after assessments have started.
To opt-in to custom group roles, group roles must be defined at the root of the infoAssessment.json
file. For example:
{
"groupRoles": [
{
"name": "Manager",
"minimum": 1,
"maximum": 1,
"canAssignRoles": true
},
{
"name": "Recorder",
"minimum": 1,
"maximum": 1
},
{
"name": "Reflector",
"minimum": 1,
"maximum": 1
},
{
"name": "Contributor"
}
]
}
Attribute | Type | Default | Description |
---|---|---|---|
name |
string | - | The name of the role. |
minimum |
integer | 0 | The minimum required number of students holding this role in the assessment. |
maximum |
integer | - | The maximum required number of students holding this role in the assessment. |
canAssignRoles |
boolean | false | Allow students with this role to assign roles to other students. |
Students typically select their roles before starting an assessment, but they can change their roles mid-assessment if needed. As a safeguard against invalid role configurations, PrairieLearn prevents students from viewing questions if a group's role configuration does not meet the instructor's specification.
Adding permissions for an assessment¶
Permissions can be configured at the assessment, zone, or question level.
The schema for permissions is defined as follows:
{
"canView": ["Manager", "Reflector", "Recorder", "Contributor"],
"canSubmit": ["Recorder"]
}
Attribute | Type | Default | Description |
---|---|---|---|
canView |
Array of string | - | The names of roles that can view this part of the assessment. |
canSubmit |
Array of string | - | The names of roles that can submit this part of the assessment. |
Setting either canView
or canSubmit
to []
(empty array) means that no role can view or submit that part of the assessment, respectively. If either attribute is not set, it means that every role has the permission associated to the attribute, i.e., any student with any role can view or submit that part of the assessment.
Permissions defined at a higher level are propagated down the assessment hierarchy (assessment -> zone -> question), but permissions defined at lower levels will override those from the higher level. For example:
{
"canView": ["Manager", "Reflector", "Recorder"],
"zones": [
{
"canSubmit": ["Recorder"],
"questions": [
{ "id": "question1", "points": 1 },
{ "id": "question2", "points": 1, "canView": ["Recorder"] },
{ "id": "question3", "points": 1, "canView": ["Reflector"], "canSubmit": ["Reflector"] }
{ "id": "question4", "points": 1, "canView": null }
]
}
]
}
In the example above, question 1 can be viewed by students in Manager, Reflector or Recorder roles, but only students with a Recorder role can submit an answer, as per the default roles defined by in the assessment level (for viewing) and the zone level (for editing). Question 2 can only be viewed and submitted by a Recorder, while question 3 can only be viewed and submitted by a Reflector. Question 4 overrides the default settings by using the null
special value, and allows students in any role to view the question, though only students with the Recorder role can submit an answer.
Assigning roles to students¶
When students join a group, they are automatically assigned a role. Students can always view the roles of other students in the group, both before and during an assessment. Students can click "View role info" to see more information about the assessment's group roles.
When expanded, group assessments display information about each role, such as the min/max number of assignments and whether a role can assign other roles.
Any student with an assigner role can view additional controls to change the roles of other users in the group. Students with assigner roles can re-assign group roles both before and during an assessment.
Restrictions based on role permissions¶
When an instructor restricts the viewing of a question to certain roles, users without those roles will be unable to view that question.
Additionally, when an instructor restricts the submitting of a question to certain roles, users without those roles will be unable to submit that question.
When a role configuration is invalid, which may occur when a user leaves the group or a new user joins the group, students become unable to see any questions until the roles are reviewed. Users with both assigner and non-assigner roles can view these errors. A user with an assigner role is then expected to update the roles to fix the inconsistencies.
Forcing students to complete questions in-order¶
WARNING: We strongly discourage the use of this option during high-stakes exams, as it can be very detrimental to student success. See below for more details.
Certain assessments might be designed to be done linearly, where each question assumes that the student has completed and understood the previous question (e.g., lab worksheets). By default, PrairieLearn allows students to complete questions in any order that they like, but assessments can be configured to not allow students to view future unsolved questions.
To enable these features, set advanceScorePerc
for any question to a number between 0 and 100. An example of what this looks like is below, with boilerplate attributes omitted:
{
"zones": [
{
"questions": [
{ "id": "q1", "advanceScorePerc": 50 },
{ "id": "q2", "advanceScorePerc": 100 },
{ "id": "q3", "advanceScorePerc": 0 },
{ "id": "q4", "advanceScorePerc": 80 },
{ "id": "q5", "advanceScorePerc": 100 }
]
}
]
}
Each question blocks all later questions until its advanceScorePerc
is met. In the above example, q1
blocks all later questions until the student has scored at least 50% on it. Then q2
blocks all later questions until the student has a perfect score on it. Once a student gets past q2
, both q3
and q4
are immediately available because q3
does not do any blocking. Finally, q4
blocks the remaining q5
until the student has an 80% score on it. The advanceScorePerc
attribute on q5
is irrelevant because there are no questions after it.
The relevant score for comparing to advanceScorePerc
is the student's highest submission score for the question, not their percentage score on the question overall. For example, suppose q1
above has "points": [10, 4, 2, 1]
. Then a student who makes a 50%-correct submission on their second attempt will unblock the question, even though they only score 2 points out of 10 on the question (50% of the 4-point second-chance value). The submission score used for advanceScorePerc
is the one based on autograding components of the question and manual grading scores are not considered. For this reason a question that is purely manually graded should not have an advanceScorePerc
set on it.
An advanceScorePerc
can also be set on the zone
or assessment
level, which will act as a default for all questions in that zone or assessment. For example, the following configuration is equivalent to the above:
{
"zones": [
{
"advanceScorePerc": 100,
"questions": [
{ "id": "q1", "advanceScorePerc": 50 },
{ "id": "q2" },
{ "id": "q3", "advanceScorePerc": 0 },
{ "id": "q4", "advanceScorePerc": 80 },
{ "id": "q5" }
]
}
]
}
In the example above, q2
and q5
will have an advanceScorePerc
of 100 because the zone-level attribute is used as a default.
Note that an advanceScorePerc
of 0 is equivalent to not having the attribute at all.
For assessments that randomize the order of questions as seen by students, the advanceScorePerc
restrictions apply for each student using the question order that they were given. If a specific question order is desired then see Changing question-order randomization.
If a student uses all of their attempts on a question and cannot submit any more attempts, that question will automatically unblock, no matter what score they earned on it. This is to prevent students from getting permanently stuck on an assessment, unable to receive further credit.
Warning about in-order questions and high-stakes exams¶
The advanceScorePerc
attribute is intended to be used in group work and assessment types which are indirectly supported, such as worksheets (see multiple instance assessments). In the interest of allowing students to best demonstrate their knowledge of course material, we strongly discourage the use of this feature in high-stakes exams where the student cannot receive help from course staff.
Auto-closing Exam assessments¶
By default Exam assessments will auto-close after six hours of inactivity by the student. This generally means that you don't need to explicity close exams that students accidentally did not close when they were done. If you want to prevent auto-closing then you can set "autoClose": false
as a top-level option in the infoAssessment.json
file.
Issue reporting¶
To allow students to report issues with questions (incorrect answers, unclear wording, etc), set the "allowIssueReporting": true
property in the infoAssessment.json
file, or set it to false
to disallow reporting. This option defaults to true
.
When issue reporting is allowed, students see a button labeled "Report an error in this question" and they can submit a short text form.
Course staff see any reported issues show up on the "Issues" tab.
Access control¶
See the Access control page for details.
By default, an assessment is only accessible to course staff. To allow students to access the assessment, the allowAccess
option can be used in the assessment's infoAssessment.json
file.
Access control options can also be used to control the open/close dates of assessments and apply penalties for late submissions. Once again, see Access control page for details and examples.
Adding text and links to assessments¶
You can add a text
property to your infoAssessment.json
, which can be used to provide additional instructions, formula sheets, etc. You can use EJS syntax to access clientFilesCourse
, clientFilesCourseInstance
, and clientFilesAssessment
.
{
"text": "<a href=\"<%= clientFilesAssessment %>/formulas.pdf\">Formula sheet</a>"
}
See the clientFiles
and serverFiles
page for details about making files available to users.
Student-attached personal notes¶
By default, students can attach files to assessments as personal notes, either by uploading them or by pasting the file contents as text. This can be done on the assessment overview page, or on individual question pages. These files can be viewed by the student anytime they can view the assessment.
The purpose of this is to allow students to take extra notes during exams, for later review. For example, if a student has a Matlab script that they used to solve a question, they could attach it to that question so they can review it later.
Although we do not recommend this for regular exams, personal notes can be disabled by setting "allowPersonalNotes": false
as a top-level option in the infoAssessment.json
file. Note that this setting does not delete notes that were uploaded before the option is set, but prevents any access or modifications to them.
One particular use case for disabling personal notes can be the upload of a "formula sheet" through a separate pre-exam assessment. These uploads should take place as a regular file upload so that they can be reviewed by course staff. The assessment can then be configured so that submissions are accessible during the exam. Disabling personal notes for the "formula sheet" assessment ensures that students cannot attach any other information that they can access during an exam.
Disabling real-time grading¶
PrairieLearn is designed to give students immediate feedback on their work. However, if you wish to more closely replicate a paper exam experience, you can prevent students from grading their work as they go (what we call "real-time grading").
Note that students generally expect and benefit from having immediate feedback, so this setting should only be enabled if you have a specific reason for it.
To disable real-time grading for an assessment, add "allowRealTimeGrading": false
to the assessment's infoAssessment.json
file. This will hide the "Save & Grade" button on student question pages; only the "Save" button will be available. The "Grade saved answers" button on the assessment overview will also be hidden. Note that real-time grading can only be disabled for Exam
assessments, as immediate feedback is a core part of the Homework
experience.
An assessment without real-time grading will not show any score information during the exam. However, if a time limit is used then when it runs out the assessment will auto-grade and show students exactly which questions they got correct/incorrect. The same revealing behavior will happen if an instructor manually closes and grades the student assessment. To prevent this, set the showClosedAssessment
access rule restriction.
Disabling real-time grading changes a lot of fundamental details of how PrairieLearn is used. To account for that, the student assessment overview page displays less information about points and grading than for usual exams.
Here is the assessment page for a normal exam with real-time grading enabled:
Here is the assessment page for an open exam with real-time grading disabled:
Compared to the normal assessment, there are a number of differences:
- A warning explaining that real-time grading has been disabled is shown
- Total points is listed as a number, not as an "X/Y" score
- The percentage bar is not displayed
- The "Best submission" column is renamed to "Submission status"
- The "Available points" column has been removed
- The "Awarded points" column has been renamed to "Points" and only shows the max points
Here is the assessment page for a closed exam with real-time grading disabled:
Note that after the exam has closed and been graded, more information about points will be visible.
Limiting the number of attempts for each question¶
The number of times each student will be allowed to attempt each question can be set in different ways, depending on the type of question and assessment.
For assessments with type "Exam", each student will only be presented with a single variant of each question. The number of attempts will be determined by the points
or autoPoints
setting: if there is a single value there will be a single attempt at the question; if it is set to a list of points, then there will be one attempt for each value in that list. In other words, the number of attempts is determined based on the number of values in the list of points.
For assessments with type "Homework", students will be presented with an unlimited number of attempts for each question. By default, every new attempt corresponds to a different variant of the question, unless:
- the question is set to
"singleVariant": true
in the question configuration file. In this case, students will get unlimited attempts for the same variant.
-
the
triesPerVariant
setting is set as below. In this case, the student will have the set number of attempts to correctly answer the question. Once the student answers the question correctly, or the number of tries per variant is exhausted, the student will be given the option to try a new variant."zones": [ { "questions": [ {"id": "singleAttemptQ", "points": 10}, {"id": "tryOncePerVar", "points": 10}, {"id": "tryThreeTimesPerVar", "points": 10, "triesPerVariant": 3} ] } ],
Limiting the rate at which answers can be graded¶
Practice is important in learning and there should be room for mistakes and learning from them. Immediate feedback can help as it can give feedback despite the limited human resources. However, to prevent mindless trial-and-error problem solving, controlling resubmissions can be an effective tool (Ihantola et. al., Review of Recent Systems for Automatic Assessment of Programming Assignments).
One way to limit the amount of feedback provided to students is to limit the rate at which graded submissions are allowed. This can be done by using the gradeRateMinutes
setting. If set, this value indicates how long a student needs to wait after grading a question to resubmit a new answer to the same question for grading. Students are still able to save a submission, but are not able to grade until either the waiting time has elapsed, or when they close the assessment. By default, this value is set to 0, which means that there is no limit.
The gradeRateMinutes
value can be set for each specific question in the assessment. It can also be set for a zone or the full assessment, in which case it will apply individually to each question in the zone or assessment. In other words, if the assessment has a grading rate set, once a student submits an answer for grading in one question, they have to wait to submit new answers to that question, but they are able to grade other questions in the meantime.
"zones": [
{
"gradeRateMinutes": 30,
"questions": [
{"id": "canOnlySubmitEvery30minutes", "points": 10},
{"id": "canOnlySubmitEvery60minutes", "points": 10, "gradeRateMinutes": 60},
{"id": "canSubmitAnytime", "points": 10, "gradeRateMinutes": 0}
]
}
],
Honor code¶
By default, Exam
assessments require students to certify their identity and pledge an honor code before starting the assessment:
- I certify that I am
name
and I am allowed to take this assessment. - I pledge on my honor that I will not give or receive any unauthorized assistance on this assessment and that all work will be my own.
To disable this requirement, set "requireHonorCode": false
as a top-level option in the infoAssessment.json
file.
The text of the honor code was based on the University of Maryland's Honor Pledge and the University of Rochester's Honor Pledge for Exams. This is a "modified" honor code (McCabe et al., 2002), as opposed to "traditional" codes that typically also require students to report any violations of the honor code they observe.
Linking to assessments¶
Some instructors may wish to publish links that point students directly to their assessments on PrairieLearn. These links may be published in course web pages, LMS systems like Compass or Canvas, or sent to students via email or other messaging platforms. Instructors should note that the URL listed on the browser points to the instructor view of an assessment, which is typically not accessible to students.
The appropriate link to provide to students can be found by opening the "Settings" tab of the Assessment. This page includes, among other useful information, a Student Link that can be provided to students. This link points students directly to the specific assessment, enrolling them automatically in the course if they are not yet enrolled.
Client fingerprint tracking and changes¶
While a student is working on an assessment, PrairieLearn tracks the user's IP address, session ID, and user agent (this includes the operating system, browser application, and version). These attributes together make up a client fingerprint. The fingerprints are then recorded during events while accessing the assessment instance. For example, when a student views a question, a record of the client fingerprint is saved along with the view event.
While an assessment is open and active, each time the client fingerprint is recorded, PrairieLearn checks it against the previous client fingerprint used to access that assessment. PrairieLearn will track and display how many times the fingerprint has changed during the course of the assessment. You can see the number of times a fingerprint changed on the Students tab of an assessment. You can also see more detailed information about the client fingerprint by accessing the student's assessment instance and reviewing the Fingerprint column of the event log.
Some fingerprint changes may occur naturally during the course of an assessment, such as a computer connecting to a different Wi-Fi access point or a student changing locations while working on homework. However, a high number of changes in an exam-like environment, while the assessment is in progress, could be a possible indication of collusion between students. In particular, many fingerprint changes could be an indication that multiple users were accessing the exam simultaneously, such as one student in the exam room and a second student outside. In such a case, the exact pattern of fingerprints in the assessment instance log will be helpful in determining whether there is indeed an academic integrity issue.
The fingerprint change counter is only updated while the assessment is open and active. Once the assessment is closed, fingerprints are still tracked, but the count of fingerprint changes is no longer updated since, once the assessment is closed, students will only be able to access the assessment for review, with no new submissions. Access through different devices or browsers at this point does not commonly raise a concern of possible misconduct.