How do you calculate item discrimination index in SPSS?
Determine the Discrimination Index by subtracting the number of students in the lower group who got the item correct from the number of students in the upper group who got the item correct. Then, divide by the number of students in each group (in this case, there are five in each group).
What is the difference between difficulty index and discrimination index?
Item difficulty is the percentage of learners who answered an item correctly and ranges from 0.0 to 1.0. The closer the difficulty of an item approaches to zero, the more difficult that item is. The discrimination index of an item is the ability to distinguish high and low scoring learners.
How do you do Cronbach’s alpha in SPSS?
To test the internal consistency, you can run the Cronbach’s alpha test using the reliability command in SPSS, as follows: RELIABILITY /VARIABLES=q1 q2 q3 q4 q5. You can also use the drop-down menu in SPSS, as follows: From the top menu, click Analyze, then Scale, and then Reliability Analysis.
How do you check validity and reliability of data in SPSS?
What is validity and reliability in SPSS?
Validity: a characteristic of measurement concerned with the extent that a test measures what we actually wish to measure. • Reliability: a characteristic of measurement concerned with accuracy, precision and consistency.
How do you do item analysis?
It is computed by adding up the number of points earned by all students on the item, and dividing that total by the number of students. The standard deviation, or S.D., is a measure of the dispersion of student scores on that item.
What is Rasch measurement model?
The Rasch model is used to measure latent traits like attitude or ability; It shows the probability of an individual getting a correct response on a test item. The Rasch model is a lot simpler and intuitive than many other models.
How is Rasch model calculated?
The fit of data to the Rasch model can be evaluated by calculating how much is “left over” after the data have been used to estimate item difficulties di and person abilities bn = br, where r is the test score of person n.
What is the best difficulty index?
Results. The difficulty index of MCQ ranged from 0.67 to 0.79, which is considered as optimal level. The difficulty index for Long Case ranged from 0.89 to 0.91, which is considered as less optimal level.
What is item analysis with SPSS software?
Item analysis with spss software. WHAT IS ITEM DISCRIMINATION? • Generally, students who did well on the exam should select the correct answer to any given item on the exam. • The Discrimination Index distinguishes for each item between the performance of students who did well on the exam and students who did poorly.
What is SPSS Statistics?
SPSS Statistics is a leader in statistical software. The IBM SPSS® software platform offers advanced statistical analysis, a vast library of machine-learning algorithms, text analysis, open-source extensibility, integration with big data and seamless deployment into applications.
What is item difficulty in SPSS?
Item analysis with spss software. ITEM DIFFICULTY • Item difficulty is simply the percentage of students who answer an item correctly. In this case, it is also equal to the item mean. Diff = # of students choosing correctly total # of students • The item difficulty index ranges from 0 to 100; the higher the value, the easier the question.
How to conduct data analysis on SPSS?
If you are worried about conducting your data analysis on SPSS, here are a few guidelines and an overview of the process. Load your excel file with all the data. Once you have collected all the data, keep the excel file ready with all data inserted using the right tabular forms.