This question has been asked many times thru the centuries. I believe the answer is yes. Though, I personally have never seen a ghost, I have had personal paranormal experience's with deceased family members. One only needs to conduct their first EVP session to become a believer also and understand communication to an extent is a real possibility with the beyond.
Here are a few reason's why a human spirit may decide to stay behind and not go to the light that is shown to them when they die.
1) Genuine Love: A spirit can become distressed because of the mourning it may see a loved one going thru. It will try to show that all is ok and not to worry.
2) Not giving Permission: A persons love can be so strong for another, that it does not allow a spirit to pass over even if it wants to. Permission must be granted to the departed to move on.
3) Violent or Sudden Death: This type of death leaves a spirit not realizing that the physical body is dead and it will go back to familiar surroundings
4) Danger: A spirit may stay behind because it feels it needs to warn or protect a loved one from something that might cause harm.
5) Unfinished Business: Whatever the situation might be, they have things that they feel need to be completed before they leave.
6) Eternal Damnation: A truely evil person, such as a criminal or killer's spirit will stay on the spirit 'plane' because it does not want to be thrust into hell for it's past sins.
7) Greed: Possession over land or money has been known for a human spirit to remain behind because of the attachment to material things.
8) Burial: Improper burial or desecration of burial site. Many homes have been built on old cemeteries, most home owners maybe unaware for many reasons.
