"Statistical Sampling" Question

Reply #6

mitachoo — Tue, 04 Jun 2019 11:07:30 GMT

Thanks so much for walking me through this, this gives me more than enough to go on.

Reply #5

Raven62 — Tue, 04 Jun 2019 11:05:06 GMT

The main types of probability sampling methods are simple random sampling, stratified sampling, cluster sampling, multistage sampling, and systematic random sampling.

https://www.wyzant.com/resources/lessons/math/statistics_and_probability/introduction/sampling

Reply #4

cottoneyedjoe — Tue, 04 Jun 2019 05:26:44 GMT

The first step is to convert everything in the first row back to raw numbers rather than percentages. You have

observed values

1 : 104

2 : 101

3 : 115

4 : 122

5 : 107

6 : 110

7 : 132

8 : 115

9 : 122

Next, you compute the expected values. Since you said each of the nine root sums should occur with a theoretical probability of 1/9, the expected values are

expected values

1 : 114.222

2 : 114.222

3 : 114.222

4 : 114.222

5 : 114.222

6 : 114.222

Reply #3

mitachoo — Tue, 04 Jun 2019 01:13:50 GMT

Allright. I checked out the link and this is a little beyond me. Perhaps walking me through an example might help. Here's a snapshot of some of my data:

Looking at the first row, there are 1,028 observations, with 9 possible outcomes (p = 11%). What I'm trying to determine is if there is any statistical significance in some of the larger discrepancies from 11%. Can I say, for example, that the occurrence of Root Sum 2, at 9.8%, is sufficiently below the expected value of 11% such that I c... [ More ]

Reply #2

mitachoo — Tue, 04 Jun 2019 00:55:58 GMT

Super, I will check it out, thanks

Reply #1

cottoneyedjoe — Mon, 03 Jun 2019 17:41:35 GMT

What you want is called a chi-squared test. https://en.wikipedia.org/wiki/Chi-squared_test

I could walk you through how to calculate the error and its statistical significance for a specific set of data, but if you are more mathematically inclined than average you can probably figure it out on your own from the wiki article and other sources. It's built-in to Excel I believe.

Edit: More specific article https://en.wikipedia.org/wiki/Pearson%27s_chi-squared_test

"Statistical Sampling" Question

mitachoo — Mon, 03 Jun 2019 04:21:19 GMT

Hi all! I have a Statistical Sampling -type question.

I have an event for which I assume P = 1/9, and I've taken N measurements to try and determine if P is in fact 1/9. My question is this: what is the relationship between N and the error band around the measured P? What I'm doing is a long and convoluted story, but in a nutshell, I'm looking at data that shows a particular Pick 3 strategy likes certain Root Sums more than others, and I'm trying to convince myself that this is (or is not) an... [ More ]