# Split-group validation

## Compare independent groups of randomly assigned participants

The split-group validation method is a fairly straightforward process. Run inferential statistics using your dataset. Then, randomly assign members of the dataset to either a derivation group or a confirmatory group. The split between the two independent groups can be 50/50, 60/40, or 70/30. Run the same inferential statistics on both the derivation group and the confirmatory group. If the findings are similar, then you can assume validity for the original findings. That is the basic methodology for split-group validation. Use

__as a platform for randomization in split-group validation.__**randomizer.org**### Split-group validation in SPSS

Unlike the

Here are the methods for splitting the study participants into the derivation and confirmatory datasets:

1. Click on the

2. Click on

3. In the

4. Click on the

5. In the

6. If researchers want to use a 50/50 split-group method, type the number

7. Click

8. Click

9. Back in the

10. The observations denoted as

11. Run statistical analyses on the two groups independently. If the results are similar, then validity evidence for the original statistical findings is assumed.

**technique available in SPSS, the split-group validation technique is not a button that is clicked. Instead, it is a simple recode conducted using the**__B__ootstrap...**drop-down menu at the top of the screen.**__D__ataHere are the methods for splitting the study participants into the derivation and confirmatory datasets:

1. Click on the

**drop-down menu.**__D__ata2. Click on

**to select it.**__S__elect Cases...3. In the

**Select**table, click on the**Ran**button to select it.__d__om sample of cases4. Click on the

**button.**__S__ample...5. In the

**Sample Size**table, click on the**button to select it.**__A__pproximately6. If researchers want to use a 50/50 split-group method, type the number

**50**into the**% of all cases**box. For 60/40, type the number**60**. For 70/30, type the number**70.**7. Click

**Continue.**8. Click

**OK**.9. Back in the

**Data View**window, scroll all the way to the right of the database to find a variable denoted as**"filter_$"**10. The observations denoted as

**"0"**can be codified as the derivation group and the observations denoted as**"1"**can be codified as the confirmatory group.11. Run statistical analyses on the two groups independently. If the results are similar, then validity evidence for the original statistical findings is assumed.

## Hire A Statistician - Statistical Consulting for Students

**DO YOU NEED TO HIRE A STATISTICIAN?**

Eric Heidel, Ph.D.** **will provide the following statistical consultingservices for undergraduate and graduate students at $50/hour. Secure checkout is available with Stripe or PayPal.

- Statistical Analysis
- Research Design
- Sample Size Calculations
- Diagnostic Testing and Epidemiological Calculations
- Survey Design and Psychometrics