I was 9 at the time, staying home sick from school, and no one else was there, they were either at school or at work. My dad had just come home for lunch and then left again, I was laying on the couch and as soon as he left I fell asleep, well I'm not sure how long passed, it couldn't have been too long, but I felt someone slap me, and I woke up. Opening my eyes I expected to see my dad standing there, but as my eyes gained focus, there was no one standing there, or anywhere in the room, and while I was looking around to see what hit me, another slap came across my face, forcing my head to look sideways, then it was gone. I couldn't feel anything in the room, and I didn't feel scared before, or after it happened, it was really like, it happened, and then there was nothing there. When I had checked in the mirror afterword there were red hand shaped welts across my face, so I know it wasn't the result of hallicunating on waking up suddenly and being disoriented. Which is also what lead me to go upstairs and check my face in the mirror for marks in the story of the woman in white and both times, there was definitely proof that someone or something had touched me.
I'm not relating this directly to my encounter but there was a story in that Hell House book about entities in Jamaica called duppies, which come from the result of certain religious practices, and in one story there is a guy who sees a woman who gets slapped by something that doesn't seem to be there, and the next minute she is dead. Getting slapped when I was 9 by something that wasn't physically there , didn't kill me, obviously, but after reading that book, years after my experience, it made me very interested.