A "digital signature with partial recovery" is a special kind of digital signature, with one advantage: it often adds less overhead to the length of a signed message, compared to other digital signatures.
For example, if you sign a 100-bit message with 2048-bit RSA (without any support for message recovery), then the length of the signed message will be 100+2048 = 2148 bits. On the other hand, if you signed that message using a scheme with partial message recovery, the length of the signed message might be (for instance) 2048 bits.
The exact impact on message length depends upon various parameters: for instance, the length of the message, the length of the signature field, the amount of message recovery supported. So I can't give you a simple formula to tell you how much of an advantage "partial recovery" will be in any particular application setting.
But this tells you in what circumstances you might be interested in a "digital signature with partial recovery": namely, those where the impact on message lengths is critical. (In those circumstances, you might also want to look at ECC digital signature schemes, and compare the impact on message lengths in your particular application.)