# How do you do a KR20 in SPSS?

## How do you do a KR20 in SPSS?

The steps for conducting Kudar-Richardson 20 (KR-20)

1. The data is entered in a within-subjects fashion.
2. Click Analyze.
3. Drag the cursor over the Scale drop-down menu.
4. Click on Reliability Analysis.
5. Click on the first dichotomous categorical item to highlight it.
6. Click on the arrow to move the item into the Items: box.

What is KR 21 method?

Kuder-Richardson Formula 21 (KR-21) Similarly to KR-20, K is equal to the number of items. Difficulty level of the items (p), is assumed to be the same for each item, however, in practice, KR-21 can be applied by finding the average item difficulty across the entirety of the test.

### What is the difference between KR20 and kr21?

KR-20/KR-20 are measures of test reliability, Kuder-Richardson Formula 20, or KR-20, is a measure reliability for a test with binary variables (i.e. answers that are right or wrong). The KR20 is used for items that have varying difficulty. For example, some items might be very easy, others more challenging.

What is the difference between KR20 and coefficient alpha?

Both KR20 and Cronbach’s alpha are measures of internal consistency (broadly referred to as coefficient alpha). If items are not binary (e.g., test questions where examinees may receive partial credit), KR20 is not appropriate and Cronbach’s alpha is the better choice.

## How do you calculate KR 21?

The formula for KR21 for scale score X is K/(K-1) * (1 – U*(K-U)/(K*V)) , where K is the number of items,U is the mean of X and V is the variance of X.

What is a good KR score?

KR-20 scores range from 0-1 (although it is possible to obtain a negative score); 0 indicates no reliability and 1 represents perfect test reliability. A KR-20 score above 0.70 is generally considered to represent a reasonable level of internal consistency reliability.

### What is a KR value?

KR-20 (Kuder–Richardson Formula 20) is an index of the internal consistency reliability of a measurement instrument, such as a test, questionnaire, or inventory.

What is a good KR 20 score?

These high-stakes exams are expected to maintain consistent KR-20 scores higher than 0.80. With smaller sample sizes, course exams with a KR20 score higher than 0.60 to 0.65 should be considered consistent and reliable, while it is recommended to maintain scores higher than 0.70.

## What is a good Cronbach’s alpha?

The general rule of thumb is that a Cronbach’s alpha of . 70 and above is good, . 80 and above is better, and . 90 and above is best.

Is 0.6 Cronbach alpha acceptable?

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.

### Where to find kr21 _ info in SPSS Statistics?

The Aggregate procedure is available under Data->Aggregate. After running Aggregate, the KR21_info data set will will be listed in the Windows menu of SPSS Statistics and can be activated by clicking that item. The Compute command operation is available under Transform->Compute Variable.

Where can I find the kr21 data set?

All of the steps in the KR21 calculation can be performed in the menu system, or graphic user interface (GUI). The Aggregate procedure is available under Data->Aggregate. After running Aggregate, the KR21_info data set will will be listed in the Windows menu of SPSS Statistics and can be activated by clicking that item.

## What is the purpose of IBM SPSS Statistics 21.0?

IBM SPSS Statistics 21.0 focuses on increasing the analytic capabilities through: Building better models from uncertain inputs while assessing risk using Monte Carlo simulation techniques. Providing faster performance with more accurate results, increased productivity and effectiveness using a range of specialized techniques.

How to calculate the kr21 formula in Excel?

The Aggregate procedure is used to compute the pieces of the KR21 formula and save them in a new data set, (kr21_info). With that new data set active, a Compute command is then used to calculate the KR21 coefficient.. /SUMMARY=TOTAL MEANS VARIANCE. compute Nitems = nvalid (item1 to item6).