The Miniature Goldendoodle is not a purebred dog. It is a cross between the Golden Retriever and the Toy, Miniature or small Standard Poodle. Some Miniature Goldendoodles are being bred as a first cross between a Golden Retriever and a Miniature Poodle. Some have Toy Goldendoodle in it. These two smaller sizes of Goldendoodles are achieved sometimes by surgical insemination or artificial insemination, but not all breeders perform this method of breeding. The resulting puppies may or may not be miniature in size. The theory is that they will be somewhere in between the Miniature Poodle's size and the Golden Retriever's size. The best way to determine the temperament of a mixed breed is to look up all breeds in the cross and know you can get any combination of any of the characteristics found in either breed. Ask the breeder you contact which method of breeding they used to produce the Mini Goldendoodle. Not all of these designer hybrid dogs being bred are 50% purebred to 50% purebred. It is very common for breeders to breed multi-generation crosses.
There are a few different ways breeders are producing Goldendoodles.
F1 = 50% Golden Retriever and 50% Poodle: This is Golden to Poodle cross; this is first generation, resulting in healthier offspring. Hair type can be smooth like a Golden or wavy/shaggy or occasionally wiry like an Irish wolfhound (but with a softer feel); they can shed or not shed; pups in the same litter can vary.
F1-B = 25% Golden Retriever and 75% Poodle (F1 Goldendoodle and Poodle cross): This is Goldendoodle bred back to Poodle.
F2 = F1 Goldendoodle and F1 Goldendoodle cross: With this combination you get the same percentage of Golden Poodle mix as you would an F1 Goldendoodle.
F3 = F2 Goldendoodle and F2 Goldendoodle cross.
Multi-generation = F3 or higher generation Goldendoodle and F3 or higher generation Goldendoodle cross.