Science

sendero

(28,552 posts) Wed Apr 16, 2014, 08:05 AM Apr 2014

Can someone help with a statistical problem?

Ok, I understand stats at a gut level but am totally untrained as to performing equations to solve practical problems. I suspect this is easy and I'm asking for a stats DUer to help

The problem:

! have 100 widgets. All of the widgets are either red or blue.

I select 3 widgets randomly. All of the widgets I selected are blue.

What is the implied percentage of blue widgets out of the 100?

Hopefully, I have stated a problem that can be solved with the information presented

5 replies

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Highlight:

Can someone help with a statistical problem? (Original Post) sendero Apr 2014 OP

100%, but... DetlefK Apr 2014 #1

Thanks! sendero Apr 2014 #2

You sure you want to open that can of worms? DetlefK Apr 2014 #3

Don't spend any time on it.. sendero Apr 2014 #4

Using the binomial distribution, and trying out different probabilities . . . StatGirl Apr 2014 #5

DetlefK

(16,423 posts)

1. 100%, but...

Reply to sendero (Original post)

Wed Apr 16, 2014, 08:24 AM

Apr 2014

This number is only true with a certain probability ("confidence&quot . The actual value lies somewhere in a confidence-interval around those "100%".

As your sample-size increases to encompass more of the whole set, the confidence-interval shrinks until only the true value is left.

EDITED

sendero

(28,552 posts)

2. Thanks!

Reply to DetlefK (Reply #1)

Wed Apr 16, 2014, 08:29 AM

Apr 2014

Is it possible to state a "margin of error" for this scenario?

My example mirrors a real-life situation and so I cannot have more than 3 in my initial sample.