Pokemon Go Study: PokeStops

We are often asked, "Do some PokeStops give out different egg species?" or "Do some PokeStops give out more 10km or 2km Eggs?"

Because of the difficulty in gathering this data, the world has been in the dark regarding PokeStop egg drop rates and distributions. We still don't know all the answers, but today we get to share a new, significant finding!

26 Silph Researchers undertook a grueling task: each researcher collected and hatched 50 eggs from a single Pokestop, allowing us to analyze whether different Pokestops gave different eggs. Nearly all 26 researchers managed to acquire the target 50, and some managed to get up to 180. In total 1,841 eggs were hatched, and the contents have been recorded and analyzed.

SUMMARY

After analysis, we are confident that not all Pokestops award eggs from the same distribution.

In other words, we witnessed some travelers receiving significantly more 2k eggs and others receiving significantly more 5k eggs from their PokeStop of choice! We can't yet say why, but the fact that not all PokeStops were observed to give out the same egg odds is a big deal. Look forward to more research as we continue learning about PokeStops and Eggs.

Now for the fun part: how we arrived at our conclusions!

ANALYSIS

First, we examined the distribution of egg-distances (ie, 2km, 5km, or 10km) for eggs from each PokeStop. One important reason for starting with this is because the distance is already determined at the PokeStop and the hatching location cannot have any influence on it. The distribution for each researcher is given in the following table:

Immediately, we suspected that not all PokeStops are awarding egg-distances from the same distribution. Here is a look at the ratio of 2km eggs to 5km eggs:

We decided to run a chi-squared test for independence on the data. This test checks whether it's plausible that the distance distribution is independent of PokeStop. We unfortunately obtained very few 10km eggs, so we are unable to include these in the test (See Note 1). So we looked only at the distribution between 2km and 5km eggs. This left a total of 1,715 eggs to analyze, 669 2km eggs and 1,046 5km eggs.

The first step of the chi-squared test is to calculate the expected number of 2km and 5km eggs for each researcher, based on their total number of hatches and the egg distribution of all trainers. Then we will test whether these expected counts differ significantly from the observed (actual) counts.

Source:http://www.pokeaccountbuy.com/news/112--pokemon-go-study-pokestops-and-egg-distances