WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

AUTHOR

Dr. Alistair Ward

DESCRIPTION

• Defines the weightings, associated with each of the soft-constraints, used to compare & select between alternative lesson-definitions, at each stage in the construction of a timetable.
• Hard-constraints (e.g. that a student or teacher can't be in more than one place at a time, or that the capacity of a location can't be exceeded), are never violated, & so don't need to be quantified for subsequent comparison.

Types

Type-synonyms

Data-types

data LessonCriteriaWeights w

• The weight of various criteria used to select a lesson from alternatives, at specific coordinates in the timetable.
• These criteria relate only to the attributes of the lesson rather than its coordinates in the timetable; since the latter is common to all alternatives.

Constructors

MkLessonCriteriaWeights

Fields

• getWeightOfAreResourcesReused :: CriterionWeight w

  A lesson is preferred, if the required resources (locations & teachers) are shared with other student-bodies, by merging them into a single larger student-class.

• getWeightOfGreatestMinimumConsecutiveLessons :: CriterionWeight w

  A lesson is preferred, if the course to which it belongs, has a greater minimum consecutive lessons; since this makes it harder to book later, into the smaller spaces remaining.

• getWeightOfGreatestRemainingCourseLessons :: CriterionWeight w

  A course is preferred, if it has greater unbooked lessons, since a course requiring only one lesson can be booked on any day.

• getWeightOfGreatestSynchronisedCourseSetSize :: CriterionWeight w

  A course is preferred, if it is a member of a larger set of synchronised courses; it seems prudent to book the most constrained course's lessons, early.

• getWeightOfIsCoreKnowledgeRequirement :: CriterionWeight w

  A subject is preferred, if it is categorised by the student, as a core knowledge-requirement.

• getWeightOfIsSpecialistInTopic :: CriterionWeight w

  A teacher is preferred, if their specialtyTopic is the proposed topic.

• getWeightOfMatchCourseClassSizeToLocationCapacity :: CriterionWeight w

  A location is preferred, when its capacity matches the course's optional maximum class-size.

• getWeightOfMaximiseRelativeFacilityUtilisation :: CriterionWeight w

  A location is preferred, the more its facilities are used; cf. getWeightOfMinimiseWasteOfScarceFacilities, which tries to make a distinction based on the type of the wasted facility.

• getWeightOfMaximiseStudentClassSizeOverCourseClassSize :: CriterionWeight w

  A course is preferred, the more any maximum class-size is filled by the proposed student-class. CAVEAT: this can change retrospectively given getPermitTemporaryStudentBodyMerger.

• getWeightOfMaximiseStudentClassSizeOverLocationCapacity :: CriterionWeight w

  A location is preferred, the more its capacity is filled by the proposed student-class. CAVEAT: this can change retrospectively given getPermitTemporaryStudentBodyMerger.

• getWeightOfMinimiseBookingAtAnotherCoursesSpecifiedTime :: CriterionWeight w

  A booking-time is preferred, if there's minimal probability that courses for other the knowledge-requirements of this student-body & any studying synchronised courses, will specifically request that time; the probability becomes a certainty for those knowledge-requirements which can only be satisfied by one course, allowing corresponding lessons to be filtered from all candidate-lessons, before this evaluation.

• getWeightOfMinimiseBookingOfLocationByOtherTeachers :: CriterionWeight w

  A location is preferred, when booked by the fewest other teachers.

• getWeightOfMinimiseDeviationFromTimeslotRequest :: CriterionWeight w

  A course is preferred, if it is booked closer to any timeslot-request.

• getWeightOfMinimiseInterCampusMigrationsOfStudents :: CriterionWeight w

  A course is preferred, if inter-campus migrations of students are minimised.

• getWeightOfMinimiseInterCampusMigrationsOfTeachers :: CriterionWeight w

  A course is preferred, if inter-campus migrations of teachers are minimised.

• getWeightOfMinimiseStudentBodyCombinations :: CriterionWeight w

  A lesson is preferred, when the number of student-body combinations is minimised. CAVEAT: potential conflict with getWeightOfMaximiseStudentClassSizeOverLocationCapacity & getWeightOfMaximiseStudentClassSizeOverCourseClassSize.

• getWeightOfMinimiseTeachersLocusOperandi :: CriterionWeight w

  A location is preferred, if the size of teacher's locus-operandi is minimised; based merely on the number of distinct locations booked, rather than the distance between them.

• getWeightOfMinimiseWasteOfScarceFacilities :: CriterionWeight w

  A lesson is preferred, if the location's unused facilities, are commonly available elsewhere; cf. getWeightOfMaximiseRelativeFacilityUtilisation, which treats all facilities equally.

Instances

Eq w => Eq (LessonCriteriaWeights w)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

(==) :: LessonCriteriaWeights w -> LessonCriteriaWeights w -> Bool

(/=) :: LessonCriteriaWeights w -> LessonCriteriaWeights w -> Bool

Show w => Show (LessonCriteriaWeights w)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

showsPrec :: Int -> LessonCriteriaWeights w -> ShowS

show :: LessonCriteriaWeights w -> String

showList :: [LessonCriteriaWeights w] -> ShowS

NFData criterionWeight => NFData (LessonCriteriaWeights criterionWeight)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

rnf :: LessonCriteriaWeights criterionWeight -> ()

Num w => Default (LessonCriteriaWeights w)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

def :: LessonCriteriaWeights w

(XmlPickler w, Ord w, Real w) => XmlPickler (LessonCriteriaWeights w)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

xpickle :: PU (LessonCriteriaWeights w)

(Eq w, Num w) => SelfValidator (LessonCriteriaWeights w)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

getErrors :: LessonCriteriaWeights w -> [String]

isValid :: LessonCriteriaWeights w -> Bool

(Eq criterionWeight, Num criterionWeight) => CriterionWeights (LessonCriteriaWeights criterionWeight)

Defined in WeekDaze.ExecutionConfiguration.LessonCriteriaWeights

Methods

areAllZero :: LessonCriteriaWeights criterionWeight -> Bool

Constants

associationList :: [(String, LessonCriteriaWeights w -> CriterionWeight w)]

The ordered list of tags & accessors.

tag :: String

Used to qualify XML.

weightOfAreResourcesReusedTag :: String

Used to qualify XML.

weightOfGreatestMinimumConsecutiveLessonsTag :: String

Used to qualify XML.

weightOfGreatestRemainingCourseLessonsTag :: String

Used to qualify XML.

weightOfGreatestSynchronisedCourseSetSizeTag :: String

Used to qualify XML.

weightOfIsCoreKnowledgeRequirementTag :: String

Used to qualify XML.

weightOfIsSpecialistInTopicTag :: String

Used to qualify XML.

weightOfMatchCourseClassSizeToLocationCapacityTag :: String

Used to qualify XML.

weightOfMaximiseRelativeFacilityUtilisationTag :: String

Used to qualify XML.

weightOfMaximiseStudentClassSizeOverCourseClassSizeTag :: String

Used to qualify XML.

weightOfMaximiseStudentClassSizeOverLocationCapacityTag :: String

Used to qualify XML.

weightOfMinimiseBookingAtAnotherCoursesSpecifiedTimeTag :: String

Used to qualify XML.

weightOfMinimiseBookingOfLocationByOtherTeachersTag :: String

Used to qualify XML.

weightOfMinimiseDeviationFromTimeslotRequestTag :: String

Used to qualify XML.

weightOfMinimiseInterCampusMigrationsOfStudentsTag :: String

Used to qualify XML.

weightOfMinimiseInterCampusMigrationsOfTeachersTag :: String

Used to qualify XML.

weightOfMinimiseStudentBodyCombinationsTag :: String

Used to qualify XML.

weightOfMinimiseTeachersLocusOperandiTag :: String

Used to qualify XML.

weightOfMinimiseWasteOfScarceFacilitiesTag :: String

Used to qualify XML.

Functions

calculateWeightedMean

Arguments

:: (Fractional weightedMean, Real criterionValue, Real criterionWeight)

=> LessonCriteriaWeights criterionWeight

-> Criterion criterionValue

areResourcesReused: Maximum if the proposed lesson already exists at the same time in other student-body timetable, & therefore allows resource-reuse, by merging them into a student-class.

-> Criterion criterionValue

minimumConsecutiveLessons: Maximum when the proposed lesson, belongs to a course which specifies the greatest possible minimum consecutive lessons.

-> Criterion criterionValue

remainingCourseLessons: Maximum when the number of lessons required for the course matches the number of days the student & teacher are mutually available, falling to minimum when there are fewer remaining lessons.

-> Criterion criterionValue

synchronisedCourseSetSize: Maximum if the course is a member of the largest possible set of synchronised courses.

-> Criterion criterionValue

isCoreKnowledgeRequirement: Maximum if the subject is categorised as a core knowledge-requirement for the student, otherwise minimum.

-> Criterion criterionValue

isSpecialistInTopic: Maximum if the teacher is a specialist in a given topic, otherwise minimum.

-> Criterion criterionValue

matchOfCourseClassSizeToLocationCapacity: Maximum when the maximum class-size specified for the course matches the capacity of the location, falling to minimum as the deviation increases.

-> Criterion criterionValue

relativeFacilityUtilisation: The number of facilities used (regardless of their nature), over the total number of facilities available at the location.

-> Criterion criterionValue

studentClassSizeOverCourseClassSize: The number of students in the class, over the course's maximum class-size; this makes little sense if the class-size can grow.

-> Criterion criterionValue

studentClassSizeOverLocationCapacity: The number of students in the class, over the location's capacity; this makes little sense if the class-size can grow.

-> Criterion criterionValue

bookingAtAnotherCoursesSpecifiedTime: Maximum when if there's zero probability that courses for this student-body's other knowledge-requirements, will specify the proposed booking-time.

-> Criterion criterionValue

bookingOfLocationByOtherTeachers: Maximum when the location has been booked by zero other teachers, tending to minimum as each additional teacher books a lesson in this location.

-> Criterion criterionValue

deviationFromTimeslotRequest: Maximum when the proposed booking-time matches a timeslot-request for the course, falling to minimum as the deviation rises.

-> Criterion criterionValue

interCampusMigrationsOfStudents: Maximum when the campus for the proposed booking matches that in which the student is located in adjacent time-slots.

-> Criterion criterionValue

interCampusMigrationsOfTeachers: Maximum when the campus for the proposed booking matches that in which the teacher is located in adjacent time-slots.

-> Criterion criterionValue

studentBodyCombinations: Maximum if there's no increase in the number of student-body-combinations for the proposed lesson, falling towards minimum with each additional student-body-combination.

-> Criterion criterionValue

teachersLocusOperandi: Maximum if either the teacher has no previous bookings, or their locus operandi is unchanged, falling towards minimum with large relative increases to the locus operandi.

-> Criterion criterionValue

wasteOfScarceFacilities: Maximum if the proposed lesson either doesn't waste any facilities, or failing that merely wastes those which are ubiquitous.

-> Writer [Maybe criterionValue] weightedMean

The individual criteria values, & their weighted mean.

• Returns the weighted sum of the specified criteria, divided by the sum of the weights.
• Each criterion increases in proportion to some desirable attribute of the proposed lesson.
• Each criterion should be in the same range of magnitudes, so that none dominates the total, thus making the total a clear measure of the value attributed to each.
• The magnitude of the value of each criterion should be independent of the dimensions of the problem, such that the balance isn't disturbed when it's changed; i.e. they should be dimensionless.
• Lessons lacking the concept being measured shouldn't be disadvantaged, but assigned a constant median magnitude.

Mutators

perturbWeights

Arguments

:: (Enum f, Fractional f, Real f, Show f, Random f, RandomGen randomGen)

=> randomGen

-> f

The magnitude of the random perturbation; resulting in an increase or a decrease, by a factor of up to (1 + x) .

-> Mutator f

• Perturb each weight by an independent random value, of configurable magnitude.
• Under this transformation, criterion-weights of zero will remain unchanged.

zeroWeightOfGreatestMinimumConsecutiveLessons :: Num w => Mutator w

zeroWeightOfGreatestSynchronisedCourseSetSize :: Num w => Mutator w

zeroWeightOfIsCoreKnowledgeRequirement :: Num w => Mutator w

zeroWeightOfIsSpecialistInTopic :: Num w => Mutator w

zeroWeightOfMatchCourseClassSizeToLocationCapacity :: Num w => Mutator w

zeroWeightOfMaximiseRelativeFacilityUtilisation :: Num w => Mutator w

zeroWeightOfMaximiseStudentClassSizeOverCourseClassSize :: Num w => Mutator w

zeroWeightOfMaximiseStudentClassSizeOverLocationCapacity :: Num w => Mutator w

zeroWeightOfMinimiseBookingAtAnotherCoursesSpecifiedTime :: Num w => Mutator w

zeroWeightOfMinimiseBookingOfLocationByOtherTeachers :: Num w => Mutator w

zeroWeightOfMinimiseDeviationFromTimeslotRequest :: Num w => Mutator w

zeroWeightOfMinimiseInterCampusMigrationsOfStudents :: Num w => Mutator w

zeroWeightOfMinimiseInterCampusMigrationsOfTeachers :: Num w => Mutator w

zeroWeightOfMinimiseTeachersLocusOperandi :: Num w => Mutator w

zeroWeightOfMinimiseWasteOfScarceFacilities :: Num w => Mutator w