How are item Analysed?

How are item Analysed?

Item analysis is a process which examines student responses to individual test items (questions) in order to assess the quality of those items and of the test as a whole. Following is a description of the various statistics provided on a ScorePak® item analysis report.

What does an item discrimination index of 0 tell you?

If an item has a discrimination index of 0, it indicates it is not discriminating at all – i.e. the same number of people in the higher group got it correct as in the lower group.

How do you determine whether the test item is ambiguous?

The test item is a potential miskey if there are more students from the uppergroup who choose the incorrect options than the key. Ambiguous item happens whenmore students from the upper group choose equally an incorrect option and thekeyed answer.

What are the different types of test items?

Five test item types are discussed: multiple choice, true-false, matching, completion, and essay. Information covers the appropriate use of each item type, advantages and disadvantages of each item type, and characteristics of well written items.

What does high discrimination index mean?

Discrimination Index – The discrimination index is a basic measure of the validity of an item. It is a measure of an item’s ability to discriminate between those who scored high on the total test and those who scored low.

What is internal consistency in research?

Internal consistency refers to the general agreement between multiple items (often likert scale items) that make-up a composite score of a survey measurement of a given construct. This agreement is generally measured by the correlation between items.

What is a good test item?

A good test item is comprehensible. Reading difficulty and choice of vocabulary should be as simple as possible relevant to the grade level being tested. In the same way, the wording of a good test item should be “invisible”. It should be simple, clear, and not a distraction from the concept at hand.

What is internal consistency reliability in research?

Internal consistency reliability is a way to gauge how well a test or survey is actually measuring what you want it to measure. You send out a survey with three questions designed to measure overall satisfaction. Choices for each question are: Strongly agree/Agree/Neutral/Disagree/Strongly disagree.

What is a good item discrimination index?

The index is represented as a fraction and varies between -1 to 1. Optimally an item should have a positive discrimination index of at least 0.2, which indicates that high scorers have a high probability of answering correctly and low scorers have a low probability of answering correctly.

What is item difficulty and item discrimination?

The two most common statistics reported in an item analysis are the item difficulty, which is a measure of the proportion of examinees who responded to an item correctly, and the item discrimination, which is a measure of how well the item discriminates between examinees who are knowledgeable in the content area and …

What is internal and external consistency?

Internal consistency is the consistency between different parts of an interface; External consistency is consistency with other applications on the same platform, or with standards out in the world.

What is the most common test for internal consistency?

Cronbach’s alpha: The most commonly used measurement of internal consistency. Split-halves test: Involves splitting the test items in half (i.e., forming a group of all even items and another group with all of the odd items) and correlating the two halves.

What are test items?

A test item is a specific task test takers are asked to perform. For example, an item may test one point (understaning of a given vocabulary word) or several points (the ability to obtain facts from a passage and then make inferences based on the facts). Likewise, a given objective may be tested by a series of items.

What is an acceptable level of reliability?

A general accepted rule is that α of 0.6-0.7 indicates an acceptable level of reliability, and 0.8 or greater a very good level. However, values higher than 0.95 are not necessarily good, since they might be an indication of redundance (Hulin, Netemeyer, and Cudeck, 2001).

What is an example of consistency?

The definition of consistency means thickness or something stays the same, is done in the same way or looks the same. An example of consistency is a sauce that is easy to pour from a pitcher. An example of consistency is when paint is applied uniformly so that the wall looks the same from one side to the other.

What is a good reliability score?

Test-retest reliability has traditionally been defined by more lenient standards. Fleiss (1986) defined ICC values between 0.4 and 0.75 as good, and above 0.75 as excellent. Cicchetti (1994) defined 0.4 to 0.59 as fair, 0.60 to 0.74 as good, and above 0.75 as excellent.

What is a good difficulty index?

11, 12 Discrimination index of 0.40 and up is considered as very good items, 0.30–0.39 is reasonably good, 0.20–0.29 is marginal items (i.e. subject to improvement), and 0.19 or less is poor items (i.e. to be rejected or improved by revision).

What is the internal consistency method?

Internal consistency reliability refers to the degree to which separate items on a test or scale relate to each other. This method enables test developers to create a psychometrically sound test without including unnecessary test items.

What is a good internal consistency score?

Cronbach’s alpha

Cronbach’s alpha Internal consistency
0.9 ≤ α Excellent
0.8 ≤ α < 0.9 Good
0.7 ≤ α < 0.8 Acceptable
0.6 ≤ α < 0.7 Questionable