Have you found an answer that wasn't posted here yet? I have the same issue.
When making a new document. First change to inches then change the resolution you want and hit enter (it has to be done like this or the size will change). Once you've done that you can then paste into the document and it should match. So if it says Width & Height in pixels and resolution 72 ppi. First change from pixels to inches then change to 300 ppi or whatever resolution you want. It has something to do with going from inches in Illustrator to pixels in photoshop, so if the default is pixels it will resize it to pixels at 72 ppi rather than 300 ppi, but if you change it to inches it will transfer it as inches rather than pixels. Hope this helps.
Illustrator doesn't have a resolution. The raster effect resolution is what you get if you rasterize some vector art inside of Illustrator. It has nothing to do with your copy and paste to Photoshop.
1. Copy your object from Illustrator
2. Switch to Photoshop and choose 'New'
3. Make sure the height and width is set to Inches as shown in the screen grab.
4. Change the resolution to whatever you need, probably 300 ppi.