This year JAMB introduced the Item Response Theory (IRT) which they said would reduce guessing. This sparked some questions about how it works. I will attempt to answer all questions i have seen on Nairaland. Feel free to ask more questions.

What is Item Response Theory:
Item Response Theory posits that the probability of a random person (P) with an ability (A) answering a random question (Q) with difficulty (D) correctly is conditioned upon the ability of the person and the difficulty of the item. In other words, if a person has a high ability in a particular field, he or she will probably get an easy question correct.

How does it work:
The student is asked a question of moderate difficulty level and then if the student answers this question correctly, the next question is more difficult. If that question is answered incorrectly, then the next will be easier.

How is my score calculated
Your score depends on how many questions you answered correctly and the difficulty of the questions.

How can it stop guessing
This is a question everyone was asking. I have a short and a long answer. The short answer is: No, it won't stop guessing. A multi-choice test answers will always be guessable. The long answer is: Yes, it can reduce the success rate of guessing. Here are some ways:

- Some question correct answer are easily guessable. By eliminating irrelevant options. IRT funtion(see below) takes into account item guess-ability and can offer better questions.

- Correct guesses will take you to places you can't maintain. Remember, the more correct answers the higher the difficulty. You will (might) end up falling back to your real level (score).

Any benefits:
- Take less time
- Give more accurate score
- Enjoyable by students (You get questions that you have about 50% chance of answering)
- Student are not presented with the same questions (Reducing collabo with neighbors as the way you answer questions will be different from your neighbor).

The Future/Challenges:
The major challenge will be properly calibrating questions (their difficulty, guess-ability, etc). It takes time and IRT soft-wares are expensive. This year, I believe JAMB didn't fully use IRT, but in the future (from next year), I believe it will be used throughout as they have gotten feedback/data this year and have much time to fully refine it.

The IRT formular:
The item response function of the 3PL model is:

b – difficulty, item location
a – discrimination
c – pseudo-guessing

How do I Prepare for Exams Now:
CBT apps and some textbooks will be less effective in preparing you for JAMB.

We have built a personalizing learning platform that is based on the same IRT software JAMB uses and will be launching it soon. It provides adaptive lessons that adapt to your level and the way you learn best. It like no other exam preparation app in Nigeria and will be a direct alternative to JAMB lessons.

We will be offering it for free to our first 100 users from Nairaland, so hurry now and register:

http://prepup.co

cc: lalasticlala, abdulahi001

elvis10ten:
This year JAMB introduced the Item Response Theory (IRT) which they said would reduce guessing. This sparked some questions about how it works. I will attempt to answer all questions i have seen on Nairaland. Feel free to ask more questions.

What is Item Response Theory:
Item Response Theory posits that the probability of a random person (P) with an ability (A) answering a random question (Q) with difficulty (D) correctly is conditioned upon the ability of the person and the difficulty of the item. In other words, if a person has a high ability in a particular field, he or she will probably get an easy question correct.

How does it work:
The student is asked a question of moderate difficulty level and then if the student answers this question correctly, the next question is more difficult. If that question is answered incorrectly, then the next will be easier.

How is my score calculated
Your score depends on how many questions you answered correctly and the difficulty of the questions.

How can it stop guessing
This is a question everyone was asking. I have a short and a long answer. The short answer is: No, it won't stop guessing. A multi-choice test answers will always be guessable. The long answer is: Yes, it can reduce the success rate of guessing. Here are some ways:

- Some question correct answer are easily guessable. By eliminating irrelevant options. IRT funtion(see below) takes into account item guess-ability and can offer better questions.

- Correct guesses will take you to places you can't maintain. Remember, the more correct answers the higher the difficulty. You will (might) end up falling back to your real level (score).

Any benefits:
- Take less time
- Give more accurate score
- Enjoyable by students (You get questions that you have about 50% chance of answering)
- Student are not presented with the same questions (Reducing collabo with neighbors as the way you answer questions will be different from your neighbor).

The Future/Challenges:
The major challenge will be properly calibrating questions (their difficulty, guess-ability, etc). It takes time and IRT soft-wares are expensive. This year, I believe JAMB didn't fully use IRT, but in the future (from next year), I believe it will be used throughout as they have gotten feedback/data this year and have much time to fully refine it.

The IRT formular:
The item response function of the 3PL model is:

b – difficulty, item location
a – discrimination
c – pseudo-guessing

How do I Prepare for Exams Now:
CBT apps and some textbooks will be less effective in preparing you for JAMB.

We have built a personalizing learning platform that is based on the same IRT software JAMB uses and will be launching it soon. It provides adaptive lessons that adapt to your level and the way you learn best. It like no other exam preparation app in Nigeria and will be a direct alternative to JAMB lessons.

We will be offering it for free to our first 100 users from Nairaland, so hurry now and register:

http://prepup.co

cc: lalasticlala, abdulahi001

well explained, this write-up is front-page worthy.

abdulahi001:


well explained, this write-up is front-page worthy.

it won't make front page since it doesn't contain Tonto dike or snake.

Magical my foot!.... GRE WANNA BE BUNCH.... Nigerian examination system is failed... Is it the same jamb that they paste answers on nairaland?

Lol.