A college classroom, with a graduate student by a projector and a few professors seated in the chairs. The graduate student in social sciences was presenting the results of a survey they had designed and administrated themselves. The student adjusted the projector.
"Here was the next question from the survey: 'What is a fun activity a husband and wife can do together?' The question gave one line for a freeform answer."
There were some muffled chortles from the professors. The student flipped to the next page, showing the results.
"50% of respondents answered 'Sex'. 20% answered 'Shopping', 10% 'Painting the house', 10% 'Cooking', 10% 'Rearranging furniture'.
The professors stared at this for awhile.
"What do you conclude from this?" asked Dr. Green.
"Well, obviously, about half of couples like sex. The other half like home decoration, and shopping."
"That's rather optimistic," said Professor Blau.
"Did you capture the gender of the respondents?" asked Dr. Schwartz.
"No," said the student. "Responses were anonymous."
"Did you interview both spouses of each couple?"
"Oh, no, it was just 100 people who professed to be married."
"Where did you find the people to survey?"
"They were customers at the Happy Pins Bowling Alley, on couple's night. There are 25 teams of 2 couples each. To pay for my graduate studies, I have a job there handing out shoes."
"So ..." said Dr. Schwartz, pausing to doublecheck their logic, "there were 25 teams, comprising 50 couples, which is 100 people, and 100 of those people took the survey ... so by the pigeonhole principle you DID capture responses from both spouses of each couple ... ?"
"Ah ... yes, I suppose so."
"And can we conclude that there were 50 men and 50 women?"
"No, not necessarily! ... but yes, in this case, I believe that was true."
"I have an alternative hypothesis," said Professor Blau. "That 100% of the men answered 'Sex', and 100% of the women answered shopping or home decorating. That there were no couples with shared interests at all. I believe that is also compatible with your data."
The student frowned. "That's rather pessimistic." Some pacing. "Unfortunately, I did not gather enough data to distinguish between our two hypotheses. That would be a good thing to test in further research."
"All these couples were bowling together in a bowling league," said Dr. Schwartz. "It's surprising that none of them listed 'Bowling' as an answer. Do you have any theories on why?"
"You're right," said the student. "Now that you point that out, that does seem rather inexplicable. Maybe they disqualified it, since it is more an individual or team activity rather than a couple activity? Hm. Or maybe they all don't like bowling as much as sex and home decorating?"
"Are you sure this data isn't all just fabricated?"
"No! Honest! It's as real as I am!"
"Hmmm..."
"Are you married?" asked Dr. Green.
"No, I've somehow never been interested in any of that." answered the student. "I'm a confirmed single, I suppose."
"What were you expecting to find?" asked Dr. Schwartz.
"Well, married couples are a bit of a mystery to me," said the student. "That was part of my motivation in asking. I was hoping, actually, that they'd answer 'playing scrabble' or the like."
"Scrabble?"
"It really is better when played with an opponent," answered the student.
"Perhaps you could ask whether they were happily married?" asked Professor Blau.
"Actually, I did ask that! That's the next question! It allowed a yes/no answer."
The student flipped to the next page, "Are you happily married?", then to the next page showing the results.
"50% of respondents said they were happily married, 50% were not."
Dr. Schwartz probed. "Does that rule out the couples having the same interests?"
"No," answered the student. "Although having a shared interest may contribute to happiness, it is not the only factor, and people may have many interests. Happiness and having shared interests aren't necessarily correlated."
"Do you know the correlation of the questions, that is, of the people who answered 'Sex', how many were happily married?"
"Yes I do!" answered the student. "That was quite remarkable. There was 100% correlation: those who answered 'Sex' were unhappy, while those with other answers were happy."
"So what do you conclude?" asked Dr. Green.
"Half of couples are happy, half are not. Having sex is not a firm basis for a happy marriage, while shopping and home decorating are."
"I'm afraid I have an alternative hypothesis again," piped up Professor Blau. "The same one as before, in fact. That all the women are happy because they're making their husbands shop and home decorate, and all the men are unhappy because they're not getting sex."
More pacing. "Both hypotheses seem compatible," said the student. "Again, I'm afraid, I don't have enough data to distinguish between the two possibilities."
"This survey seems to be raising more questions than it answers," said Dr. Green.
"It is fertile grounds for future research," answered the student. "This was intended as an exploratory study all along. 100 people can give suggestive results, but it is usually not enough to make statistically significant conclusions."
The professors argued with themselves, while the student flipped to the next question, "What would you like to do with your in-laws."
This story, and all its data, are completely made up. I don't know what the real answers to these questions would be. A month after I wrote this story, I used this as a response to a reddit WritingPrompts prompt, "A lawyer, a philosophy student, and a psychologist walk into a bar ..." That was the closest I found to an acceptable prompt for this story in a month. All the particulars are wrong, but that prompt called for about this sort of discussion. WritingPrompts is way too superhero-oriented.