# Refining the dataset

Before you start training and creating models, you need to pre-edit them. If you notice any flaws in your dataset after uploading the files, you can easily correct them in our app.

Dataset with errors
Dataset with errors
In the dataset above, you can see several errors. Let's correct them.

Rename the dataset
Rename the dataset
First, you need to rename the whole dataset. TOYS is not a good descriptor for a collection of photos of office accessories. Let's replace it with the name ACCESORIES by clicking the pen icon next to the dataset name.

Enter the appropriate name and confirm the change by clicking the save icon.

Delete the image
Delete the image
One of the images does not contain any of the items you are interested in. You can delete it completely by hovering over the image in question and clicking on the trash can icon that appears. Confirm by clicking OK.

Narrow down the image selecion
Narrow down the image selecion
If you only want to view one category of images, such as SQUISHY_TOY, narrow down the selection by clicking on the relevant tag above the image preview.

Select multiple categories/tags
Select multiple categories/tags
If your photos have more than one category/tag assigned to them, you can select and look through them in one view.

The word 'flashlight' written in lower case
The word 'flashlight' written in lower case
The word flashlight is written in lower case. To unify this tag with the rest, edit the name in the Category manager.

Category manager
Category manager
When a new window appears, click the edit icon on the line with the tag name. Enter the corrected name FLASHLIGHT and confirm the change by clicking the save icon.

Finished dataset
Finished dataset
You may have noticed that some of the images do not have categories. We will show you how to deal with this problem in the Classification tutorial.