Looking for Maths / Conceptual Help forums

[Jtucker10278]

I guess I'm looking for a place that can help me with general maths/conceptual help.

I don't know if there is a place here to post/discuss this type of stuff or if anyone can recommend another forum


Example 1.

Weighted Averages -

Movie and TV ratings on IMDB are rated 0.0 through 10.
however something that has an average rating of 7 that has been rated by 50,000+ people is probably better than something that has an average rating of 8.5 but only rated by 650 people.

So I understand the concept of weighted averages and how to do it in excel but I am clueless about how much "weight" to give in this instance.


Example 2.

Employee Productivity Charts -

I have employees who build different kinds of widgets,

Sarah Builds Widget Type A faster than she builds Type B or C

Tom Builds Widget Type A just as fast as Sarah But he also builds Type C faster than anyone.

How do I Show this on a Graph or Chart?

Again I understand how to make charts in excel I just don't know the best way to represent this data

thanks for any thoughts

 

[Joe4]

Regarding example 1, there are a lot of factors that come into play. Quite frankly, assuming that your sample populations are representative (and not biased in any way), 650 is a pretty darn big sample size, and I wouldn't expect to see that much difference between those results and 50,000+ people. If there is a sizable difference, it probably points to some sort of inherent bias in one of the sample sets. If there is, you really cannot have any sort of confidence in it.

From this link here: https://www.qualtrics.com/blog/determining-sample-size/, you can see that a sample size of 385 would give you a pretty high-level of confidence.

The math for trying to weight this sort of thing can get pretty complex, as you can see here: https://stats.stackexchange.com/que...etermine-the-weight-of-different-sample-sizes

Unfortunately, my degree is not in Advanced Statistics, so there is not much more I can say about it, but a Google search did pull up these forums, which maybe a good place to check:
http://mymathforum.com/advanced-statistics/
https://mathhelpboards.com/advanced-probability-statistics-19/
http://www.talkstats.com/

Good luck!