Once you have created a model, you'll be redirected to the Settings tab:
Here, you can adjust a conversion window, manage value assignment to the channels, and set up each step of the conversion funnel.
Conversion window is a period of time before each conversion. Value is attributed only to sessions of this period.
By default, this parameter is set to 10 days. But time to purchase can be different for your project. Before changing the parameter we recommend take a look at “Time Lag” report in Google Analytics. It shows how many days pass from the first visitor's interaction to a purchase.
The field “Index of custom dimension that contains User ID” is required if Google BigQuery Export for Google Analytics is a source of your attribution model.
To check that index please open Administrator menu in your Google Analytics account and choose Custom Definitions → Custom Dimensions.
Assign value not to all the channels
There is an option to assign value of specific traffic channels to the previous channel in the conversion path. This option is described in more details in the article “Set channels that should not get value assigned”.
After you set up parameters of your model, you can proceed to setup of funnel steps.