Syd's Science Project

Thanks to all those who helped Sydney with her science fair project.  Its finally finished!  Congratulations to Jordan Jackson who got the closest guess, within 4 skittles.  I'm sure you're all dying to know how many skittles were in this thing...well here you go.  The following was written by Sydney, as it appeared on her science poster:

GUESS THE RAINBOW

The Wisdom of the Crowds

In 1907, Sir Frances Galton got a big, strong, heavy ox and said if you guess this ox’s weight, I will take it to a butcher so he could take the meat out of the ox so it could be yours. Everyone was so excited to guess. the numbers were big, and the numbers were small.  There were 787 guessers, but no one got it right.

Sir Francis Galton went into his house and found the mean (average) of everybody’s guess and found that it was one pound off of the real ox’s weight!!

I wanted to do this because I thought it would be interesting to try it out. Instead of an ox’s weight, I used skittles in a container.

Question:

Is a group of people better at making guesses than individuals?

Hypothesis:

I think the average guess of a group of people will be closer than a random individual person when guessing the number of Skittles in a jar.

Materials:

1. a plastic container
2. Skittles
3. $10.00 gift card for the winner
4. Ballot box
5. Guessing cards

STEPS:

1. I filled a jar with Skittles.

2. My mom counted the Skittles from the jar and wouldn’t tell me or else I might influence the people in getting a closer number than what they thought.

3. My dad and I went to a mall to ask people to write down their guesses for the Skittles.
-I also asked friends.
-My dad also took it to work to ask his fellow co-workers.
-My dad also set up a blog so people could do their guesses on the internet.

4. After that, we added all the numbers up (all 144 guesses) and got 57,621. Then we found the mean which is 400 and compared it to the actual number of Skittles, which is 469.
-I also found the mean for the ages: 17 and under, and 18 and older.
-The mean for 17 and under is: 424
-The mean for 18 and older is: 388

5. after all that, we made a stacked bar graph of 18 and older guesses, and 17 and under guesses.

DATA (results):

1. Total of “in person” guesses: 36,373
Participants: 92    Average guess: 395

2. Total of “online” guesses: 21,248
Participants: 52    Average guess: 408.6

3. Total of Overall guesses: 57,621
Participants: 144    Average guess: 400

4. 18 and older average: 388

5. 17 and younger average: 424

Actual number of Skittles: 469

(WINNER) Closest guess: 473

Number of participants who did as well or better than the total average guess: 28 (19.4%)

Did the results match the hypothesis?

The results DID match the hypothesis because only 28 out of the 144 people got closer to the actual number than the number than the mean got. Even though I thought the mean would be closer.