B.Ed. Notes-Educational Management - MODULE III- Managing evaluation in school

EDU. 106. EDUCATIONAL MANAGEMENT

MODULE III- Managing evaluation in school

Prepared by

SABARISH-P

M.Sc., M.Ed., JRF & NET

Assistant Professor in Physical Science, Arafa Institute for Teacher Education

Attur, Thrissur.

Contact me : pklsabarish@gmail.com

Ø  Measurement-Meaning

•         Measurement is the process by which we ascertain the quantity of a thing

•         It is the assignment of a numerical index to the thing we assess

•         To measure means to determine the magnitude of something in terms of suitable unit.

•         It is an act or process that involves the assessment of a numerical index to whatever is being assessed.

Ø  Measurement – Definition

•         “Measurement is the process of assigning symbols to dimensions of phenomena in order to characterize the status of a phenomena as precisely as possible” - M. Brad field

Ø  Evaluation-Meaning

•         Evaluation is the process by which we judge the value or quality of something.

•         It is the process of determining the extent to which an educational objective attained.

•         It is the systematic process of determining to what extent the educational objectives are being realized

Ø  Evaluation - Definition

•         “Evaluation is the assignment of symbols to phenomenon in order to characterize the worth or value of a phenomenon, usually with reference to some social, cultural or scientific standards” -James . M. Brad field

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Ø  Distinction between Measurement and Evaluation

.

Measurement	Evaluation
Quantitative	Quantitative + Qualitative
It measure ‘how much’ achieved	It measure ‘how good’ achieved
Not depend upon the purpose	Always depend upon the purpose
Describes a situation	Judges a situation
Not continuous	Continuous
Objective & Impersonal	Subjective & Personal
Scope is limited	Scope is unlimited

Ø  Purpose/Functions of Evaluation

•Assessment

•Placement

•Certification

•Diagnosis

•Prognosis

•Guidance

•To provide information for grading, reporting to parents and promoting students

•To evaluate the effectiveness of a single teaching method or to apprise the relative worth    of several methods.

•To motivate the students

•To select the students

•To evaluate the entire educational institution and to show how several of its aspects could   be improved.

•To collect information for effective educational vocational counseling.

Ø  TYPES OF EVALUATION

1. Formative Evaluation

2. Summative Evaluation

1) Formative Evaluation

•         Formative evaluation is the process by which the achievement of the pupils is judged at every stages of the teaching-learning process.

•         It involves immediate feedback.

•         Formative Evaluation will motivate the pupil for better performance.

•         Formative Evaluation helps the teacher in diagnosing the difficulties of pupils and in modifying teaching strategies.

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2) Summative Evaluation

•         Summative evaluation is one administrated to pupil at the end of the lesson or unit of learning.

•         Helps the teachers and pupils to know how far they have succeeded in realizing the pre-determined educational objectives.

•         Summative evaluation includes classification, gradation and certification of learners in terms of their total attainment.

•         Summative evaluation helps in organizing the total system of education more effectively.

•         Summative evaluation may be conducted at the end of a term and cover number of learning units.

•         Annual examination also may be said to be summative in nature.

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Ø  Distinction/Difference between Formative and Summative Evaluation

Formative Evaluation	Summative Evaluation
Conducting during the process of instruction	Conducting at the end of a lesson or chapter
Aim to evaluate the learning process	Aim to evaluate the final output of learning
Take place continuously in the course of instruction	Usually Takes place in regular intervals ie, weekly,monthly or yearly
Implementing through teacher observation, oral questioning etc	Purpose is placement, certification etc. Implementing through tests, Exams etc

Ø  

TOOLS & TECHNIQUES OF EVALUATION

TOOLS	TECHNIQUES
1.Checklist	1.Self Reporting
2.Rating Scale	2.Testing
3.Questionnaire	3.Observation
4.Inventory	4.Interview
5.Schedule	5.Case Study
6.Anecdotal Record	6.Sociometry
7.Cumulative Record	7.Projective Techniques
8.Tests

Ø  TOOLS OF EVALUATION

1.      Checklist

A checklist is a list of items for consideration. They can be in the form of questions or actions to be carried out. They can have a scoring system or they can collect comments. Checklists can speed up the collection of information by using tick-boxes and rating scales. They need to be carefully designed to make sure that when they are completed, the results are reliable and true.

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2.      Rating Scale

• Used to classify opinions and judgment regarding situation, object etc

• Rating scale refer to a scale with a set of points which describes varying degree of the dimension of an attribute being observed

3.      Questionnaire

•It is a device in the form of questions or statements

•Used for collecting factual data

•It is a systematic compilation of questions that are submitted to the person about which information is desired.

4.      Anecdotal Record

•It’s a record of informal teacher observations regarding the pupil

•It’s a record of factual descriptions of significant event in the pupil’s life

•An event in the anecdotal record is known as ‘Anec dot’

5.      Cumulative Record

•It’s a record of the complete history of the pupil

•It’s recorded cumulatively from period to period

•It gives information about physical, intellectual, social, scholastic, personality etc.

6.      Tests

•Most popular tool for collecting data for evaluation

•Classified into three

1)      Oral tests

2)      Written tests

3)      Performance test.

Ø  Types of tests

1.      Norm Referenced Tests

2.      Criterion Referenced Tests

3.      Teacher Made Tests

4.      Standardised Tests

Ø Achievement Test Construction

Steps 

1.      Planning

2.      Design

3.      Preparation of Blue print

4.      Construction of test items

5.      Preparation of the Scoring Key & Marking Scheme

6.      Question wise analysis

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Ø  Diagnostic Tests

•         It’s a test to know the difficulties, problems, inadequacies and gaps of learning of students

Ø  Remedial Teaching

•         Providing additional learning experiences that might help the child in reducing the difficulties

Ø  Construction of Diagnostic Tests

Steps

1.      Identification of problem area

2.      Content analysis

3.      Listing learning points

4.      Writing items

5.      Arranging the items

Ø Qualities of a good Test/Tool

1. Comprehensiveness

2. Objectivity

3. Objective basedness

4. Validity

5. Reliability

6. Practicability

7. Comparability

8. Discriminating power

9. Utility

1.      Comprehensiveness

•Covering all the points expected to be learnt by the pupils

•Determine the relative weightage to all the sessions and construct questions according to that scheme

2.      Objectivity

•Free from personal bias in interpreting and scoring its responses

•Means reducing subjectivity

3.      Objective Basedness

• The test should be based on pre-determined objectives.

• The test setter should have definite idea about the objective behind each item.

4.      Validity

•A test is valid, when it measure what it intends to measure

For Example

•If a test is designed to measure the linguistic ability of students, it should measure that ability

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•If the result of measurement is something else, the test is not valid

5.      Reliability

•It’s the degree of consistency and accuracy

• A test may be reliable but need not be valid. This is because it may yield consistent scores, but these scores need not be representing what exactly we want to measure.

• A test with high validity has to be reliable also. (the scores will be consistent in both cases)

• Valid test is also a reliable test, but a reliable test may not be a valid one.

Ø  Types of Validity (Not mentioned in syllabus) •Face Validity Face validity is the extent to which a test is subjectively viewed as covering the concept it purports to measure. It refers to the transparency or relevance of a test as it appears to test participants. •Content Validity If the items in the test constitute a representative sample of the total course content to be tested, the test can be said to have content validity •Construct Validity Construct validity involves explaining the test scores psychologically. A test is interpreted in terms of numerous research findings. •Congruent validity The validity of a test determined by its correlation with existing tests designed to measure the same construct. •Criterion Related Validity Criterion validity is the extent to which a measure is related to an outcome. Criterion validity is often divided into concurrent and predictive validity. Concurrent validity refers to a comparison between the measure in question and an outcome assessed at the same time. Predictive validity compares the measure in question with an outcome assessed at a later time. •Factorial Validity Factorial validity is defined as the degree to which covariance among judged traits resembles the actual or true. Ø  Different methods for determining Reliability (Not mentioned in syllabus) • Test-retest method – A test is administrated to the same group with short interval. The scores are tabulated and correlation is calculated. The higher the correlation, the more the reliability. • Split-half method – The scores of the odd and even items are taken and the correlation between the two sets of scores determined. • Parallel form method – Reliability is determined using two equivalent forms of the same test content. – These prepared tests are administrated to the same group one after the other. The test forms should be identical with respect to the number of items, content, difficult level etc. Determining the correlation between the two sets of scores obtained by the group in the two tests. If higher the correlation, the more the reliability.

6.      Discriminating Power

• Discriminating power of the test is its power to discriminate between the upper and lower groups who took the test.

• The test should contain different difficulty level of questions.

7.      Practicability

• Practicability of the test depends up on...

• Administrative ease

• Scoring ease

• Interpretative ease

• Economy

8.      Comparability

• A test possesses comparability when scores resulting from its use can be interpreted in terms of a common base that has natural or accepted meanings

9.      Utility

• A test has utility if it provides the test condition that would facilitate realization of the purpose for which it is mean.

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Ø  TECHNIQUES OF EVALUATION

1. Self Reporting

2. Testing

3. Observation

4. Interview

5. Case Study

6. Sociometry

7. Projective Techniques

1. Self Reporting

•React to items concerning his own behaviour or characteristics

•Used for measuring the traits like interest, adjustment, attitude etc

•Obtained through a check list, questionnaire, rating scale etc

2. Testing

•Commonly used technique of evaluation

•Mainly focused on cognitive traits

• Testing is a evaluation technique by which we can measure the characteristics such as knowledge, skill, intelligence, aptitude etc. of an individual or a group in a particular situation as objectively as possible.

 Purpose of Testing

• Assessment of present status of an individual

• Expressing probability of future success

• Diagnosing the causes of lack of expected performance

• For remedial measures

• For academic or vocational guidance

• Classification and comparison of individual or group

• Undertaking research to answering various questions

3. Observation

•Not mere looking

•It’s the purposeful, goal oriented perception of an object or situation

•The teacher observes the behaviors of the student, if any relevant feature notice in    behavior should be recorded as objectively as possible.

•In observation subjectivity of the observer will be often reflected in the judgment.

Different types of observation

1)      Controlled observation/Experiment: Observation under controlled condition.

2)      Uncontrolled observation: Observation of events as they naturally occur.

3)      Participatory observation: Observe the students by the observer while participating in the same activity with the students.

Merits

•Natural & Flexible

•Economical

•Easy to implement

•Can be used for all ages

Demerits

•Not possible in all conditions

•Highly subjective

•Not accurate

•It fails when the individual hide the actual behavior.

4. Interview

•Used to gather information in a face to face session regarding an individual’s experience, opinion, believes, feelings, etc

•It’s a conversation with a purpose

Types of Interviews

1.Structured Interviews

–Questions are pre-planned by the interviewer

–It is systematic

2.Unstructured Interviews

–Questions are not pre-planned by the interviewer

–It is flexible

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5. Case Study

•It is the in-depth study of a case such as an individual, a family, a community, an institution or a group

•It aims to solve the deep rooted problems

Merits

Gives holistic picture about an individual

Helps to solve the problem.

Productive in nature

Demerits

Subjective

Time consuming

Generalisation is not possible

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6. Sociometry

•J. L Moreno developed

•Its used for describing the social preferences of individuals in a group.

•It reveals the social acceptance of an individual & their inter personal relationships

•It will help the teacher to identify

STARS

•Who chosen by many

CLIQUES

•Small groups, who have chosen exclusively among themselves

ISOLATES

•Who are chosen by nobody

7.      Projective Techniques

•Used in personality assessment

•Used to collect data which cannot be collected directly from the individual

•It helps to project one’s inner feeling in an ‘unconscious’ manner

Examples for Projective Techniques

•Rorschach‘s Ink Blot Test

•Thematic Apperception Test (TAT)

•Word Association Test (WAT)

•Sentence Completion Test

•Children’s Apperception Test (CAT)

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Ø RECENT TRENDS IN EVALUATION

Ø CCE (Continuous and Comprehensive Evaluation)  & Grading System

Ø  CCE (Continuous and Comprehensive Evaluation) 

Relevance

It better covers the scope of education

Measurement of all domains

It provides Personal, vocational and academic guidance

Better reflects strengths and weaknesses of learner

It facilitate learning process

Provides immediate feedback

Reduces examination stress

Ø  Grading System

•Derived from ‘Gradus’ (Latin) means step.

•student’s level of performance is classified in to a few classificatory units using letter grades

•Classification on the basis of pre-defined standards

1. Direct Grading

•Performance is assessed in qualitative terms.

•Evaluator gives the most appropriate letter grade to each subject like A, B, C, D, E without assigning scores.

•Preferred for non-cognitive learning outcomes.

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Grade Point Average (GPA)

•It is for obtaining the overall grade of a student.

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2. Indirect Grading

•Evaluator awarding grades through marks

•Convert the mark to letter grades

•Two types

A.Absolute

B.Relative

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A.Absolute Grading

•Based on pre-determined standard which becomes a reference point for assessment of student’s performance

•Direct conversion of marks in to grades irrespective of the distribution of mark.

B.Relative Grading

•Range vary in tune with the relative position of the group

•The evaluation is done according to the level of performance of members

•Known as ‘grading on the curve’

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Ø  REFORMS IN EXAMINATION

•Semester System

•Open Book Examination

•Online Examination

Semester System

•Whole academic year is divided in to two halves

•Final examinations are held twice a year

•Continuous assessment of student’s performance

•Increased rapport between teachers and students

•Great dependency on tutorials, projects, assignments etc

Demerits

•Learning is made in to Piecemeal

•Lacks continuity

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•Administrative burden

•Increasing number of examination

•Not economic

Open Book Examination

•Allowed to bring their text books, notes and other reference materials or to access recourses and references during examination

•It may also include assigning standard set of teaching materials and examination questions before the examination so that students may prepare in advance

•It permits take home examinations without take help from others

Merits

•Less demanding on memory

•Examination becomes a learning process

•Verifies ability to retrieve information

•Enhance the comprehension and synthesizing skills

•It reduces examination anxiety

•Permits higher order questions

Demerits

•Difficult to ensure equitable recourses for all students

•Libraries usually possess few copies of the same book

•More space is needed during examinations

•Students are unfamiliar with the exam

•Clear procedures and rules are still evolving

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Online Examination

•New technique of conducting examination by using internet which facilitate the conduct of examination without face to face conduct between the examinee and examiner.

•At the same time permitting the record of the examinees' response instantaneously

Example: SBI Clerical grade exam conducting on July-August 2014

Merits

•Scoring speed

•Reduces travelling

•Reduces the chance of copying

•Can use multiple set questions

•Easier, time saving and comfortable

•Timing can be need flexible

•Minimum employ requirement

Demerits

•Good broadband facility needed

•Students acquaintance and speed on the key board is a limiting factor

•Easy manipulations or malpractices

•Need of Technical Knowledge

•Electricity/Power failure problems.

•Less freedom for selecting sections. Limited time for each section while writing exam

•Risk of loosing what has been recorded

Ø  USE OF ICT IN EVALUATION

At present the paper pencil tests are conducted for evaluating the academic performance of students. These tests are conducted in the group setting. The content coverage is poor and students cannot use them at their own. These tests are evaluated by the teachers and they may not give feedback immediately to each and every student. It may be due to this that students are unable to know their weakness and do not make any attempt to improve upon them.

ICT can be made use effectively in the evaluation. One such attempt has been made by Sansanwal and Dahiya (2006) who developed Computer Based Test in Research Methodology and Statistics. It has been titled as Test your Understanding: Research Methods and Statistics. This test can be used by individual student to evaluate his learning. The student can instantaneously get the feedback about the status of his understanding. If the answer is wrong, he even can get the correct answer. It goes a long way in improving the learning and teacher has no role to play in it. It is left up to students to use it. Such tests can be uploaded on the website for wider use. The students from other institutes can also make use of it. Not only the

students even the teachers can also use it to assess their own understanding of the subject. If used by teachers before teaching the topic, they can prepare the topic properly. Such software can be used for internal assessment. Thus, ICT can be used to improve the quality of pre as well as in-service teacher’s training.

Ø  Online Examinations can be widely used in Evaluation system.

Ø  OMR sheets can be used in Objective type tests.

Ø  Online surveys, Online interviews etc can be used in evaluation

Ø Spread Sheets

·         Is an interactive computer application programme for organization and analysis of data in tabular form.

·         Develop as computerized simulations of paper accounting worksheet.

·         Data represented as cells of an array, organized in rows and columns.

·         Spread sheets are used in computer programmes like Microsoft Excel, SPSS etc

Advantages of Using spread sheets

·         Makes the organization and consolidation of data easier.

·         Enable to calculate all basic statistics.

·         Make Graphical representation easy

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Ø BASIC STATISTICS IN EVALUATION

Ø  Statistics – Definition

“Statistics is the science which deals with collection, classification and tabulation of numeric facts as a basis for explanation, description and comparison of phenomenon” - Lovitt

“Statistics may be defined as the collection, presentation, analysis and interpretation of numerical data”- Croxten and Cowden

Statistics is the collection, classification, organisation, analysis, interpretation & conclusion of the numerical data

Ø  How it Helps/Uses of Statistics

•Collection of Data

•Classification of Data

•Organisation of Data

•Analysis of Data

•Interpretation of Data

•Conclusion of Data

Ø  Graphical and Diagrammatic representation of data

The following are commonly used graphs and Diagrams.

1. Histogram

2. Frequency Polygon

3. Frequency Curve

4. Cumulative Frequency Curve (Ogive)

a. Less than Cumulative Frequency Curve (Less than Ogive)

b. Greater than Cumulative Frequency Curve (Greater than Ogive)

5. Pie Diagram (Sector Diagram)

6. Bar Diagram

1. Histogram

 Graphical representation of continuous frequency distribution

 It is a graph including vertical rectangles with no space between the rectangles.

 The class interval taken along the horizontal axis (X – axis) and the respective class frequencies are taken on the vertical axis (Y – axis) using suitable scales of each classes.

 For each class a rectangle is drawn with base as width of the class and height as the class frequency.

 The area of each rectangle will be proportional to or equal to respective frequencies of the class

 The total area of the histogram will be proportional or equal to the total frequency of the distribution.

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2. Frequency Polygon

 It is a graphical representation of continuous frequency distribution

 It can be constructed by drawing Histogram or directly plotting the points

 To draw Frequency Polygon by drawing Histogram, join the mid-points of the top of the rectangles of the Histogram using straight lines

 Frequency Polygon can also drawn by joining the consecutive points, plotted by taking the mid-points of the classes on X-axis and corresponding frequencies on Y-axis.

 The end points are extended at each end and to join the X-axis.

 The total area under the Frequency Polygon is equal to or proportional to (numerically) the total frequency of the given distribution.

3. Frequency Curve

 It is a graphical representation of continuous frequency distribution

 It can be constructed by drawing Histogram or directly plotting the points

 To draw Frequency curve by drawing Histogram, join the mid-points of the top of the rectangles of the Histogram using smooth curve by free hand method

 Frequency curve can also drawn by joining the consecutive points, plotted by taking the mid-points of the classes on X-axis and corresponding frequencies on Y-axis.

 The end points are extended at each end and to join the X-axis.

 The total area under the Frequency Curve is equal to or proportional to (numerically) the total frequency of the given distribution.

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4. Cumulative Frequency Curve (Ogive)

It is the graphical representation of cumulative Frequency Distribution

Two types

a). Less than Cumulative Frequency Curve (Less than Ogive)

 It is the graphical representation of Less than Cumulative Frequency distribution.

 Less than Cumulative Frequency Curve is drawn by joining smoothly the points obtained by plotting the upper limit of the actual classes against their Less than cumulative Frequencies.

b). Greater than Cumulative Frequency Curve (Greater than Ogive)

 It is the graphical representation of Greater than Cumulative Frequency distribution.

 Greater than Cumulative Frequency Curve is drawn by joining smoothly the points obtained by plotting the lower limit of the actual classes against their Greater than cumulative Frequencies.

5. Pie Diagram

 Pie diagram consist of circle whose area proportional to the magnitude of the variable they present

 The component part of the variable represented by means of sectors of the circle

 The area of the sector proportional to the frequencies of the component parts of the variable.

 If A1 and A2 are the total magnitude of the two variables, to represent the data by means of Pie diagram, draw two circles with radius r1 and r2 given by

Is a circle broke down in to component sections on the basis of percentage

its used when the aggregate & their sub-divisions are to be shown together

7. Bar Diagram (simple Bar Diagram)

 Bar diagram is the simplest diagrammatic representation of data.

 They are also called one dimensional diagram.

 These diagrams are generally drawn in the shape of horizontal or vertical bars.

 The bars should be of equal breadth and the height of the bars should be proportional to the

magnitude of each quantity.

 Leave equal space between the bars.

Ø Diagrammatic and Graphic representation – Merits

 It permits easy visualization

 Easy to understand the nature of the data

 Comparative study of different aspect of a given data is possible.

 Help analysis of the data

 Help to interpret and draw conclusion

 They are interesting, attractive, and impressive

 They are the simplest method of presenting data

 They have universal validity; they are used to supply information to common man

 They give a bird’s eye-view of the entire data

 They have a great memorizing effect

Ø Diagrammatic and Graphic representation – Limitations

 It is difficult to show minor differences with their help

 Diagram can be used only to show a limited amount of information

 Diagrams show only approximate values

 It is subjective in character; its interpretation varies from person to person.

 Diagrams and graphs can be misused very easily

 Diagrams and graphs are not substitute of the original data

Ø Measures of Central Tendency

•Central Reference value

•Represents concentration of measures among a set of measures

•The value of the point around which scores tend to cluster is called ‘Measures of Central Tendency’.

•A single value that describes the characteristics of the entire data

1.Arithmetic Mean

2.Median

3.Mode

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1. Arithmetic Mean (Average)

Case – I: Ungrouped Data (Discrete data)

If x1, x2, x3, …………..xn are N observations

Arithmetic Mean – Merits

 It is rigidly defined

 AM is easy to understand

 Simple to calculate

 Based on all observations

 It is capable for further algebraic treatment.

Arithmetic Mean – demerits

 AM is affected by extreme values

 AM may lead to wrong conclusion if the figures from which it is computed are not known.

 AM can’t be calculated for a distribution having open end classes.

2. MEDIAN

 Median is defined as the middle most observation when the observations are arranged in ascending or descending order of magnitude.

Median – Merits

 It is rigidly defined

 It is easy to understand

 Simple to calculate

 It can be located by mere inspection

 It is not affected by extreme values

 It can be calculated for a distribution having open end classes

 It can be determined graphically.

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Median – demerits

 It is not based on all observations

 Median is a non-algebraic measure and hence not suitable for further algebraic treatment

 It is can’t be used for computing other statistical measures such as Standard Deviation, Coefficient of correlation etc.

 When there are wide variations between the values of different scores, a Median may not be

representative of the distribution.

3. MODE

 Mode is the value of the variable which occurs most frequently.

 In certain cases such as exact Mode may not exist or there may be Two or Three Modes in a

distribution.

 When there are Two Modes we call it Bi-Modal Distribution

 If there are Three Modes, we call it Tri-Modal Distribution.

Mode – Merits

 Easy to locate

 Not affected by extreme values

 Can calculate the Mode for the distribution having open-end classes, if open-end classes have less frequency

 It is useful in business matters.

Mode – demerits

 It is not based on all observations

 It is not capable for further algebraic treatment

 A slight change in the distribution may extensively disturb the Mode

 In a ungrouped data, if no score is repeated, it may lead to wrong conclusion that the distribution have no mode.

 As there be 2 or 3 modal values, it becomes impossible to set a definite value of a Mode.

Ø  MEASURES OF DISPERSION (MEASURES OF VARIABILITY)

 Measures of central tendency need not give an exact picture of the distribution.

 If we compare two groups, merely on the basis of the average, there is a possibility of being mislead to incorrect judgment

Eg: consider the Marks of two Groups

2, 8, 20, 28, 42 ------------------ Group 1

18, 19, 20, 21, 22 ------------------ Group 2

Here when we calculate the Mean for both groups, we get Mean = 20

But when we examine the scores, we can find that Group1 is Heterogeneous Group and

Group2 is a Homogeneous Group.

 The statistical measures used to determine the Nature and extent of dispersion of the scores are known as Measures of Dispersion or Measures of Variability.

 Measures of Dispersion measures the spreading of observations from the central value of the distribution.

Commonly used Measures of Dispersion

1. Range

2. Quartile Deviation

3. Mean Deviation

4. Standard Deviation

1. RANGE

Range is the difference between the highest and lowest scores in a Distribution.

Range – Merits

 Simplest measure of dispersion

 Easy to calculate and easy to understand

Range – Merits

 Not based on all observations.

 Very mush affected by extreme values.

 It is influenced by fluctuations of sampling.

 For open-end classes, calculation of Mode is impossible.

2. QUARTILE DEVIATION (SEMI INTER QUARTILE RANGE)

 The quartile deviation is half the difference between the upper and lower quartiles in a distribution.

 It is a measure of the spread through the middle half of a distribution.

 It can be useful because it is not influenced by extremely high or extremely low scores.

 Quartile: One of the four divisions of observations which have been grouped into four equal-sized sets based on their statistical rank.

 Lower Quartile (first quartile) Q1: first point of division of observations which have been grouped into four equal-sized sets based on their statistical rank.

 Upper Quartile (Third quartile) Q3: Third point of division of observations which have been grouped into four equal-sized sets based on their statistical rank.

 Second Quartile Q2: Second point of division of observations which have been grouped into four equal-sized sets based on their statistical rank.

 Second Quartile is called Median

This notes Prepared by SABARISH.P , Contact me : pklsabarish@gmail.com

3. MEAN DEVIATION (AVERAGE DEVIATION)

 Mean Deviation is the average of the deviations of the scores taken from the Mean

 It may be calculated by taking the deviations of each of the scores from the mean and find the average of these scores.

 Deviations may –ve or +ve, so take absolute value of deviations.

4. STANDARD DEVIATION

 Standard Deviation is the square root of the average of the squares of the deviations of the scores taken from the mean. SD denoted by the symbol σ (sigma).

 The Arithmetic Mean (Average) of the squares of deviations is known as Variance.

 Standard Deviation is the square root of the Variance.

Calculation of Standard Deviation – Steps

1. Find the Arithmetic Mean of the given data.

2. Find the deviations from Arithmetic Mean of scores.

3. Find the average of squares of deviations taken from the Mean.

4. Find the square root of the average of squares of deviations.

Standard Deviation – Advantages

 Rigidly defined

 Based on all the observations

 It is capable for further algebraic treatment

 SD is used in many advance statistical studies

 It is less affected by fluctuations in sampling

Ø  MODEL & PREVIOUS QUESTIONS

1Mark

1.Mention any two tools of evaluation

2 Marks

1.Point out two measures used for finding reliability of a test.

2.What are the functions of evaluation

3.Find the median of the scores 48,25,37,19,28,44

4.Define standard deviation

5.‘Validity is a conditions for reliability’-explain

6.Compute the mean scores of 50,32,71,64,43

7.A reliable test need not always be valid. Substantiate

8.Mention any two tools of evaluation

9.What is a test is said to be ‘objective’

10. Differentiate Formative and Summative evaluation

This notes Prepared by SABARISH.P , Contact me : pklsabarish@gmail.com

4 Marks

1.Briefly Explain ‘measures of dispersion’

2.Explain the grading system followed in our schools

3.Mention any four features of modern concept of evaluation

4.Briefly explain any two essential qualities required for a good evaluation tool

5.Write a short note on the graphical representation of statistical data

6.What are the functions of evaluation

10 Marks

1.Differentiate measurement and evaluation. What are the functions of evaluation? Explain the major techniques employed in evaluating pupil performance.

2. Differentiate measurement and evaluation. What are the functions of evaluation?

Explain the grading system followed in our schools.