What is The Singapore Theory
Most of the time, it's referred to as the Theory of Familiarization or simply Paranormal Stimuli. In essence, the theory is really basic. The method involves trying to recreate the environment, or a part of the environment, of a specific era during an investigation in an attempt to stimulate paranormal activity.
The theory, in part, is based on familiarization, believing that if spirits occupying the location recognize the environment or something positive within it, they will become active and possibly show themselves in some form. The ultimate goal is for this theory to be so effective and stimulating that the end result is an apparition.
The method is usually put into action by playing music of different eras, or one exact era if you're focusing more on an individual situation. For example, if you're in a haunted ballroom from the early 1900's, you might play music from that era. If you're in a haunted hotel or saloon in Nevada, then the music of choice would most likely be western music.
Another approach would be to recreate the environment visually. This is most often seen in 19th century victorian styles homes that have been turned into an Inn or a Bed N Breakfast, for example. It is sometimes done unintentionally by owners attempting to restore a building to it's original state, complete with antique furniture and decorations from that era. A seldom used method is to play movies from an era. Different stimuli can yield very different results, according to the theory. If you're in a location that is very old, perhaps more than 100 years, try music or movies from different eras and see if any particular one is more popular than the other.
It has been said that on numerous occasions, activity which is stimulated by this theory is of a residual nature and not active. The Singapore Theory is well-founded and based on sound principles and I think that on a good night, it would be able to stimulate active paranormal phenomena. On the other hand, one would only expect the theory to produce a residual haunt.
We as a group have never experimented with the Singapore Theory. This is something that PR will be looking into in the future.
Source of information The Paranormal Society