The General Social Survey, a comprehensive questionnaire perennially studying the habits and demographics of Americans, asks participants about their views on the afterlife. From Chicago Magazine:
in 1983 and 1984, the people running the GSS decided to ask people about their visions of the afterlife. And not just "does it exist," but specifically respondents' vision of what it's like. So they asked this:
109. People picture life after death in many different ways. We'd like to know how you think of life after death. Here is a card with sets of contrasting images. On a scale of 1-7, where would you place your image of life after death. d. 1. A pale, shadowy form of life, hardly life at all. 2. A life of complete fulfillment, spiritual and physical.
Education, political affiliation, age, and religiosity all make a difference.
Michael J. O'Loughlin
Moreover, the question does not seem to account for people who believe in reincarnation, who are a non-negligible fraction of the general population. If you are reincarnated as an earthworm, your next life will be a lot paler and more shadowy than if you are reincarnated as another human, so how should you answer if you don't know yet?
And a lot of people believe that personal identity does not survive death but spiritual energy does. How should they answer the question? If you believe your individuality will be dissolved into a huge ocean of consciousness, it could be both pale and shadowy for you and vivid and fulfilled for the ocean.
It was an interesting question, but not very carefully formulated.