WHICH IS BETTER DUNKIN’ DOUGHNUTS OR KRISPY KREME?By: Hillary Tenney (:

VS.

KRISPY KREME IS GREAT (:

My all time favorite doughnut is Krispy Kreme, they are so delicious! Although I’ve tried Dunkin’ Doughnuts and other kinds, I keep going back to Krispy Kreme because they are way better. I can definitely taste the difference and I want to see if other people can taste it too. (:

MY HYPOTHESIS

Ho: People wont be able to tell the difference between Dunkin’ Doughnuts and Krispy Kreme, therefore an equal amount of people will like each kind.

Ha: People will be able to clearly taste the difference and prefer Krispy Kreme over Dunkin’ Doughnuts.

Ho: p0 = .5

Ha: p0 > .5

SURVEY

My survey was blind and matched pairs. Since I wanted to see if people favored

Dunkin’ Doughnuts or Krispy Kreme, I asked them which they preferred as well as their gender to see if there was any correlation.

In order to make it as random as possible, I flipped a coin to see which doughnut they would try first. Heads meant they tried Dunkin’ Doughnuts first, Tails meant they tried Krispy Kreme first.

Since flipping a coin is supposed to be 50/50, it should have been fair; but when I actually did it, only 12 people tried Krispy Kreme first.

SURVEY RESULTS

Out of the 32 people that I surveyed, 20 people said that the Choice B doughnut (Krispy Kreme) tasted better.

That means only12 people picked Choice A (Dunkin’ Doughnuts).

15 out of 20 girls preferred Krispy Kreme over Dunkin’ Doughnuts. (That’s 75%)

1- PROPORTION Z TEST

z = 1.4142 p = .0786 p0 = .625 n = 32

z = 1.4142 p = .0786

The p value is about 8%. This value is significant at the 10% level but not at the 1% and 5% level.

SO BACK TO MY HYPOTHESIS…

MY HYPOTHESIS

Ho: People wont be able to tell the difference between Dunkin’ Doughnuts and Krispy Kreme, therefore an equal amount of people will like each kind.

Ha: People will be able to clearly taste the difference and prefer Krispy Kreme over Dunkin’ Doughnuts.

Ho: p0 = .5

Ha: p0 > .5

HYPOTHESIS DECISION

20 out of 32 people that I surveyed chose the Choice B doughnut (Krispy Kreme).

[That’s about 63%.] Since my result is above 50%, I must reject

my null hypothesis and assume my alternate hypothesis is correct.

OBSTACLES

Since I was limited to only surveying people in our AP Stats class and Ms. Haines’ Pre – Calc Class, it was a convenience sample.

Also, since all of the people in those two classes are between the ages of 16 and 18, I cant conclude that my results are accurate for all age groups.

DOUGHNUT PREFERENCEGUYS VS. GIRLS

Dunkin' Doughnuts Krispy Kreme0

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GuysGirls