Agatha Christie was a British novelist who wrote the Miss Marple and Hercule Poirot whodunits in the 1930s and 1940s. This was the golden era of British murder mysteries, with Arthur Conan Doyle’s Sherlock Holmes and Doctor Watson the most memorable of all. Fascinated with murder mysteries, Anthony and Elva Pratt invented a board game they called Murder! The U.S. rights were sold to Parker Brothers, who gave it the name Americans know today.
Clue is a whodunit game
Players try to solve a murder mystery by determining who did the foul deed, where the crime took place, and which weapon the murderer used.
The game board is made up to look like rooms in the murder victim’s mansion
Players move around the board, collecting clues along the way as they compete to be the first to solve the murder. The victim is the owner of the mansion where the murder took place, Mr. Boddy (get it?). Every player is a suspect.
There are six suspects
Miss Scarlet, Mrs. White, Mrs. Peacock, Mr. Green, Colonel Mustard, and Professor Plum. Their names match the colors of the tokens players use to mark their positions as they move around the board. I liked being Col. Mustard, probably because I had been a mere Sergeant.
There are six weapons
A candlestick, a knife, a lead pipe, a revolver, a rope, and a wrench.
The mansion has nine rooms
The Ballroom, Billiard room, Dining room, Lounge, Library, Study, Conservatory, Kitchen, and Hall.
Players roll a single die and move about the board in search of clues
The first to properly identify the killer, the weapon, and the room where the murder took place wins.
Winners use strategy, logic, and the process of elimination
The penalty for guessing wrong is immediate elimination from the game. This is one common form of board-game suicide.
Guessing is not a strategy, which is why winners don’t bother
Winners patiently collect enough clues and then correctly interpret them.
How many possible combinations of murderer, weapon, and location are there?
Multiply 6 possible suspects times 6 possible weapons times 9 rooms and you come up with 324 possible combinations of suspect, weapon, and room.
323 of them are wrong
If you guess, you have only one chance in 324 of being right.
Think about our 324 possible solutions
Each of them is made up of three separate components. In the game of Clue, they are the murderer, the weapon, and the room. Knowing only which weapon or room or person doesn’t get us to the answer and neither does knowing only two out of three.
To solve the mystery, we need to figure out all the components of the solution, not just some of them.
How I teach executives and researchers about sampling
The best teachers are able to connect new things to things students already know. In training sessions with individuals and groups, I use the 6 suspects, 6 weapons, and 9 locations of the Clue game to illustrate what goes into choosing a survey sample that has the necessary good cross-section of respondents.
Teams are told their goal is to conduct a survey of Consumer Attitudes in Europe
To get them started, I suggest they begin with three variables that will anchor every part of our survey: age, income, and geography. Here, workshop participants are instructed to choose scales and increments that they think will provide the best data.
Instead of six suspects, think of six different age groups:
If we sample just one of those age brackets, we eliminate five of six possibilities before we’ve even begun. If we sample three of the six age ranges, our sample will still never be representative.
For our sample to adequately stand in for the population at large, we need to choose enough from each age group
Instead of six Clue weapons, let’s think about six income brackets:
When we collect data from each of six income groups within each of six age groups, we have “solved” only 36 of 324 possible solutions, so let’s move on to our sample’s geographic composition.
Let’s think about the nine rooms in the mansion as nine European countries
The continent has more than four dozen countries and we don’t have the time and money for all of them. So for illustrative purposes, let’s choose Denmark, England, France, Germany, Italy, Netherlands, Portugal, Spain, and Turkey as our “rooms.” (Did you notice the first letters of those nine countries accidentally anagram nicely into GIFT SPEND? Me, either. I ran it through an anagram generator.)
Most companies selling products and services in Europe would be satisfied with sampling these nine countries because they are well-dispersed across Europe and more than half of the continent’s population lives in them.
Choosing countries is just Step One
Take England, for example. Three out of four studies go only to London and insist their conclusions apply to all of England. This is a typical corner-cutting strategy that makes the ridiculous assumption that London = England. Anyone who tells you this has never spent any real time there and/or is not to be trusted.
One in eight Englanders lives in London
How is it possible to draw sound conclusions about a country without bothering to find out what those other 7 are up to? If you really wanted to learn about them, go to the North East, North West, South East, South West, East Midlands, West Midlands, East, and Yorkshire regions, where seven out of eight English people live – you know, the other 60 million English consumers your competitors are ignoring.
Now we’re getting somewhere
To cover all the possibilities and not arbitrarily exclude any group from our study of Consumer Attitudes in Europe, we need to sample each of 36 age and income groups within each of our nine countries. We will then be able to compare the attitudes of people in all six age groups in all six income categories in all nine countries, 324 segments in all.
Companies that commission surveys like to see sophisticated data analytics
Most don’t know surveys can only deliver meaningful analyses when each cell in the sample matrix contains a minimum of 40 cases. Conclusions and inferences that are based on samples with fewer than 40 cases per cell are known to numbers experts to be unstable, unreliable, and untrustworthy because they violate the mathematical laws that are built into complex formulas. With a 40-case-per-cell minimum and 324 cells, we need to collect data from 12,960 respondents.
That’s outrageous!
Of course. But the point is clear. Make sure you’re confident on the front end that your survey sample will allow you dig down as deeply as you want and peel as much onion as you want to pay for.
Most studies don’t want to pay for that much detail
That’s fine as long as you have written your analytic plan in advance. Start at how you plan to use the information and work backwards. Bigger and better sample sizes cost more.
Solve your marketing problems and figure out what new products to bring to market by first determining which categories are important to investigate
You will find in almost every instance, for every product and service, your research will need to effectively sample different age brackets, income brackets, and geographies. How well you do that is up to you.
Those who don’t give enough thought to their study samples are wasting money, and worse than that, opportunity
Don’t be one of them.
Want to look at old things in new ways, see the commonplace in more detail, and hear complicated subject matter explained in simple terms?
Click here for the home page where you can scroll through the articles I’ve written every week for LetsTakeACloserLook.com since 2016. Scroll down to the bottom of this page, enter your email address, and get a new article in your inbox every Monday.
