As some have seen, when you create a new web application in SharePoint 2013, the only authentication mode available via the UI is the “Claim-based authentication.”
The reason is that Office Web Apps can work only with this model. However, it is possible to create web applications using the NTLM or Kerberos via Powershell.
To do so, you must use a command line such
New-SPWebApplication -Name "Contoso Internet Site" -ApplicationPool "ContosoAppPool" -AuthenticationMethod "Kerberos" -ApplicationPoolAccount (Get-SPManagedAccount "CONTOSO\jdoe") -Port 80 -URL "https://www.contoso.com"
More information on this subject here: http://technet.microsoft.com/en-us/library/gg276326.aspx
For application migrations, it is also possible to migrate from one mode “classic” mode “Claim-Based”, the procedure can be found here: http://technet.microsoft.com/en-us/library/gg251985.aspx
Hope this help !