In Slovenia, a country of just over 2 million inhabitants, there are over 170 active karate clubs. How are these karate clubs distributed over the area of the country? What is their market reach? Let’s find out.

UPDATE from 27th February 2017: I have published a revision to this study based on more up to date data, higher resolution datasets and a more in-depth analysis. I suggest you read the reviewed version, which you can find here: https://medium.com/@pedro.kostelec/analyzing-the-potential-market-size-of-karate-clubs-in-slovenia-revision-i-95c9a6e12321

The goal

I will begin this analysis by computing a proxy to the potential market for each of the karate clubs. I will do this by counting the number of people living closest to each karate club.

Data sources

This task makes use of the following datasets:

Population density from the Slovenian Statistics Office GIS datasets.

Coordinates of karate club in Slovenia from Klubi Slovenije.

Assumptions

This study makes some strong assumptions which may affect the results of this study.

First, I assume that most karate practitioners visit the karate club nearest to their home. This is not always a valid assumption. For example some may chose to go to a karate club nearer to their work office location.

Second, the distance between a persons’ home and karate clubs is measured as air-distance instead of driving time. Unfortunately, driving time datasets are not freely available online. This air-distance fails to consider the uneven terrain of Slovenia and the structure of its road network.

Third, I assume that the population size of each area is approximately correlated to the number of people training in karate clubs in that area.

Results

For each inhabited square kilometer I compute the distance to the nearest karate club. Then, I group this data by club and sum up the total population living in their vicinity. This total population is then our proxy for potential market size for that club.

The largest 10 clubs by potential market size are:

1 — Karate klub Shotokan Kranj (48893)

2 — Karate klub MI-KI — Oš Žirovnica (43257)

3 — AKADEMIJA BOJEVNIŠKIH VEŠČIN PTUJ (38105)

4 — Dojofit (35534)

5 — Karate klub Murska Sobota (34492)

6 — Karate klub Krka Šentjernej — OŠ BRŠLJIN (32486)

7 — DBV TO-TE Rače (30591)

8 — Karate klub Shito ryu Celje Gaberje (29963)

9 — Karate klub Ljubljana — OŠ Božidarja Jakca (29839)

10 — Karate klub Trbovlje (28857)

We can see that the top club has a potential market of almost 49000 people, which is approximately 2.5% of the entire population of Slovenia!

The distribution over all clubs looks like this:

With this, we can establish that the top 24% of karate clubs combined cover over 50% of the total Slovenian population. The top 20% of karate klubs cover just over 42%.

The map below shows how these top 10 karate clubs by potential market size stand out from the rest. These top 10 clubs are marked with large red circles, and their potential market region is colored. The blue dots represent the locations of all other karate clubs in the country. The light grey shaded area shows all the inhabited regions.