How to Stop a Spin Wheel Repeating Winners
How to Stop a Spin Wheel Repeating Winners, To stop the spin wheel from repeating the same entry, you have to choose the option that excludes the winner from further draws. With this option off, the spin wheel will repeat the same name because the draws are made from the entire list during each spin. With the option on, the names are removed after being drawn until the list is empty.
By Malik Aiesh Bahadur,
Why a wheel repeats winners
It looks like a glitch, and it is not one. A wheel has no memory. After a spin, the next spin begins at the same point on the list with the same odds, meaning the person who just won has exactly the same chances as everyone else.
With ten entries, the chances of the next spin repeating the last are 1 in 10. This does not sound like much, but the odds are stacked against you. Over the course of a ten-spin session, there are nine opportunities for consecutive repeats, and the odds of seeing at least one are actually 61 percent. You are more likely than not to see two in a row.
The classroom variation is even more damning. Spin a 25-name wheel 25 times and you would expect roughly 9 students never to be called at all, with others hearing their name twice. Teachers who take this as an indictment of the fairness of the wheel are correct to be concerned, but they are looking in the wrong place for the problem. It is the nature of randomness to produce results that seem far from it, and if every student gets a turn, the wheel is working properly. If you want different results, you will have to try a different method.
Three ways to prevent repeats
|
Method |
How it works |
Best for |
|---|---|---|
|
Remove after each spin |
The winner is taken off the wheel, and the list shrinks every spin |
Classes, turn order, anything where everyone must be picked once |
|
Full cycle, then reset |
You remove winners until the list is empty, then put everyone back for the next round |
Daily routines that run for weeks |
|
Several winners in one go |
You pick the whole group of winners at once and do not return anyone |
Giveaways with several prizes |
On Wheel Spiner, open up the Spin Wheel and enable removal after each spin prior to your first spin. If you haven't made a wheel before, how to make a spin wheel in 60 seconds shows you how to set one up.
You can also manually remove names. Spin, copy the winner into your notes, delete the line and spin again. It's slower, but it works on any tool.
What removal does to the odds
Every time someone is removed, the remaining entries get a bigger share. With 5 entries and no weights, the chances on each spin go like this.
|
Spin |
Entries left |
Chance for each entry |
|---|---|---|
|
1 |
5 |
20% |
|
2 |
4 |
25% |
|
3 |
3 |
33.3% |
|
4 |
2 |
50% |
|
5 |
1 |
100% |
Does this bias against the person who ends last? No. Because prior to any spin, every entry had an equal chance of being first, of being second, and of being last. Removing winners one by one yields a perfectly random permutation of the entire list. It is the same result as if you shuffled the list randomly, which is what the Random Order Generator does in one click. If you only need the order, and don't have an audience, do that. If you want to present it to an audience, spin.
Weighted wheels act differently, because weights are summed again after each removal. I explain that, with examples, in weighted spin wheels explained.
Picking several winners for a giveaway
For a giveaway with three prizes, spin three times with removal on. No one gets two prizes, and everyone is drawn from the winners pool fairly.
I would go further and draw alternates. Spin two or three more times and note the order so that if the first winner does not respond or is ineligible, you can immediately proceed to the next name on your list instead of redrawing. Note them in the log as first alternate, second alternate and so on.
Agree on the deadline for the winners to respond in advance and include that in the rules. The entire point of drawing alternates in advance is that no one may accuse you of favoritism.
Running a full cycle in a classroom
The simplest way to make this work is to add every student's first name to the wheel and let the wheel pick who answers and remove that name. When the wheel is empty, add the names back in and repeat.
There are a few edge cases that come up in practice
If a student is absent, remove them from the pool before you begin. A student absent may have their name come up while they are away, and you'd have to make a judgment call on whether to re-spin or not otherwise.
If a new student joins the class during the cycle, add them to the current wheel. They have an equal chance to be picked as anyone else still waiting, which isn't quite as good as the odds of those who've already been picked, but that's okay in a classroom setting. If it's a serious consequence however, you might want to wait until the next cycle to add them.
If you need a student to pass, allow them to pass, then put the name back in the wheel and continue. Do not permanently remove a name after one use.
Keep the names on the list to a first name or initial if using on a projected wheel. Nobody wants to see a wall full of names.
Keep a record of the draw
When the result matters, write it down. For a giveaway, a simple log is enough: the date and time, the number of entries, the list you used, each winner in order, and a screenshot or screen recording of the spin. Do not rely on the wheel page to remember it for you. If you close the tab, assume the state is gone, and copy the winners out before you do.
For classrooms, a tick list on paper does the job. Nothing is worse than losing track halfway through a cycle.
Common mistakes
The first is stopping removal halfway through. If you've removed twice already without it, there's already a winner on the wheel from prior spins. From the first spin onward, have the feature turned on.
The second is editing the list while the draw is in progress. Adding or removing names while it's in the middle of an active draw alters the odds for everyone who hasn't drawn yet, and it's immediately obvious to the audience. If you have to change the list, let the viewers know.
The third is accidentally removing the wrong person. To avoid this, double-check the names as you go and make sure you have the list open in a note somewhere in case you need to go back.
Finally, the last one is deciding that the wheel is rigged just because you got one repeat. It almost certainly isn't, but you can use the spin wheel tool to test it for yourself, or see the article above about how a spin wheel works to learn how to do it yourself.
Fun uses for removal mode
Elimination is a game mechanic and a fairness tool. Our Halloween party games feature Last Ghost Standing, which uses knock-out style scoring to ensure that only two players remain. The same system can be used for deciding on a restaurant, ranking movies from worst to best, or creating a single-elimination tournament bracket.
Frequently asked questions
How to avoid duplicates when spinning the wheel?
Enable the setting, which allows removing the winner from the pool after each spin. This way every participant will have a chance to win only once until the list is emptied.
Why does the wheel stop on the same name twice in a row?
Every spin is a completely independent process, where each entry has an equal chance of being chosen. So, if you have a 10 – item list, the probability of selecting the same entry twice in a row is 1/10 or 10%.
Does the option of removing the winner affect the chances?
Yes, every subsequent spin will have a higher probability of stopping on the next name. The odds will be 20, 25, 33.3%, 50 for the next five spins, if you have a 10 – item list.
Does the last entry always has the lowest chance of winning?
No, before the start of the giveaways, all the participants have an equal chance of winning. The odds will be the same for every entry in the list, if you use the spin wheel app for the first time.
How to choose multiple winners without duplicates?
Spin the wheel as many times as the number of your winners. Before each spin, make sure the option of removing the entry is enabled. After you’ve got the main prize winners, you may also want to get some alternates. For that, just make another round of spinning. Want to know more about getting multiple winners? Read this blog post: how to run a giveaway with a spin wheel.
Can I do a spin wheel lottery in random order?
Yes, you can. The order of the list can be randomized with the help of the Random Order Generator tool.
Try it
Open the Spin Wheel, paste your list, enable the removal, and start working through it. Don't have a list? There are a few pre-set wheels included in the templates. Not sure what to do with the wheel of names? Take a closer look at what it is precisely.
