Showing posts with label Test Items Analysis. Show all posts
Showing posts with label Test Items Analysis. Show all posts

Saturday, November 5, 2011

Test Items Analysis


Test Items Analysis

Definition


     The analysis of students’ responses to each item on the test is called item analysis.

 

Importance


     Item analysis data are useful in

     improving the test,

     in serving as a basis for class discussion,

      in diagnosing the students’ strengths and weaknesses, and

      in increasing the skill of item construction.

 

Item analysis deals with

 

     1. Item Difficulty

 

     2.  item Discrimination

 

     3.  and Effectiveness of distracters

 

Item Analysis Questions

 

     Does the item discriminate between the good and the poor student?

 

     2   How difficult is the item?

 

     3   How effective is each destructor in the item?

 

Steps /procedure of Item Analysis

     Step1:

 

      After scoring the test, arrange the test, papers in order, from the highest score to the lowest score.

 

     Step2:

 

     Select the 25% percent of the papers with the highest score and call at the High Scoring Group (HSG).

     Select the same number of papers with the lowest score and the call at Low Scoring Group (LSG).

     The middle group of papers is not needed in item analysis.

 

Step-3

 

 Prepare Tabulation Sheet

 

Item analysis working Sheet

Item Difficulty


     Item Difficulty definition

 

     Item Difficulty Formula

 

     Item difficulty interpretation


The difficulty of an item is defined as


     “the percentage of student who got the item right.”

 

Item Difficulty Formula

P =    H + L   (100)

N

        In which

P = index of item difficulty

H = Number of student in the high scoring   Group who got the item right

L =   Number of student in the low scoring     group who got the item right.

N = The total number of students (HSG+LSG)

 

Interpretation of I.D

     Range = 0-100

 

     Easy Item = Above 70%

 

     Moderate (Average)= 30-70%

 

     Difficult= Below 30 %

 

 

2. Discrimination Power

     Definition

     Formula

     Interpretation

Definition

The ability of the test to differentiate between good (Height Scoring) and poor (Low Scoring) students

Formula of
Discrimination Index

D   =   H     L

         N/2

In which

        D = index of discrimination

  H = Number of student in the high scoring Group who got the item right

L = Number of student in the low scoring group who got the item right.

       N = The total number of students in both (HSG+LSG)

 

Example:

   What is the Index of discrimination  of Item 3 in Above Table?

                              D   =   H     L

                                     N/2

                         D    =  7 – 2

                                    20/2

                         D    =   0.5   Answer

 

 

Interpretation

     Range = (+1)---0---(-1)

   Maximum size          Zero     Minimum Size
 

Interpretation

     Good Achievement Test should have

 

     50% of Items = Above o.40

     40% of Items = 0.40 to 0.20

     10% of Items = 0.20 to 0.00

     Zero % Items = Negative