Analysis - Suji Before vs After Riichi

Glancing through Riichi Book 1, I noticed a footnote that said people were a bit divided on whether suji before riichi was more dangerous than after or vice versa. Let's throw another data point into the ring.

Analysis - Danger of Tiles Near Dora

I wanted to do a quick analysis looking at the waits of riichis based on what the dora is, to see how much more dangerous tiles near the dora are. Instead, I ended up going a bit insane.

Analysis - Wait Reading against Open Hands

There are some popular theories about what waits are dangerous against certain calls. Let's take a look.

Analysis - Four Winds Draw

While watching a ないおトン stream, he verbally acknowledged cutting the third wind to aim for the draw, as his hand was bad. And, it worked. Let's run an analysis on this case.

Analysis - Dama vs Riichi Win Rates

I am not content with how my last dama analysis showed riichi having overall higher winrates than dama, while people still say to dama mangans. Why would I dama a mangan if it lowers my winrate? So, I'm trying again, looking at things a different way.

Analysis - Shanten Estimation by River Composition

While watching a ないおトン stream, he said, "My river looks fast." Can you actually glean meaningful information from the composition of a player's discards? Is someone who discarded only honors faster or slower than someone who only discarded middle tiles? Let's take a look.

Analysis - Taatsu Otoshi

While reading zeRo's book, I came across a chapter talking about taatsu otoshi (when people drop a two tile shape from their hand) and how it indicates the speed of their hand.

Analysis - Karagiri

 Do you like pointless data? Great! Let's look at karagiri rates in Houou games!

Analysis - Average Starting Shanten

On Amae Koromo, the stats aggregator for Mahjong Soul, it lists the average starting shanten in Jade room as being around 3.482. People thought this sounded low, so let's see the averages in Houou.

Analysis - Factors for Dama

In this analysis, we'll look at several aspects of the game and see how they affect whether a player chooses to riichi or dama a tenpai hand.

Analysis - Dama

I'm finally analyzing dama hands with the help of the drastically faster shanten calculation algorithm. Let's take a look at these mysterious creatures.

Analysis - Tenpai Chance By Tedashis and Tsumogiris

In this post, we'll look at the chance someone is tenpai based on the number of tedashis they've done, as well as what that tedashi is.

Guide - Replay Analysis

In this post, I'll go over the scripts I use to analyze replays, for anyone who also wants to try to do some analysis. Naturally, you'll need to know some amount of programming. We'll also look at a silly analysis I did which looks at the average composition of discards based on the hand's yaku.

Analysis - Flush Overflow

Today we'll be talking not about toilets, but about honitsu or chinitsu hands. It's often said that a flush hand becomes particularly dangerous once they cut the first tile of their suit (known as overflow), so let's dive into the Houou replays and see what the data says.

Analysis - Houou Stat Correlations

Do the stats of a Houou player have any correlation with each other? Does someone who calls more win more? Do they deal in more? Have lower value? Let's look at a bunch of these.

Analysis - Shanten After Calling

Someone sent me a blog post with information on the average shanten after a player makes a call, then asked if the tonpu numbers would be different. So, I recreated the code and went into more detail. What's the average shanten after someone makes their Xth call on Y turn? What about their chance of being tenpai? Does the type of call affect it? Let's see.

Analysis - Playstyle Changes Based On Lead

When you're ahead in a game of Mahjong, do you call more to try to finish hands faster and move the game along? Do you stay dama instead of calling riichi to increase your safety? Do you deal into hands that look cheap? Let's see what the Houous do.

Analysis - Tile Drop Order

Previously, I did a post about how tile danger changes based on the last two tiles of a suit a player has discarded. One thing I didn't look at in that analysis was how frequent each order was. That could be interesting, so let's take a peek.

Analysis - Disconnections

Disconnecting from a game sucks, but how much does it suck? How much is your winrate impacted based on the length of your disconnection? Let's take a look at the Houou players.

Analysis - Rates by Starting Shanten

 I was curious if hands with higher starting shanten had higher average values, so I ran some analysis to gather the data. Also included are the win rates, riichi rates, average riichi turns, and call rates for each starting shanten.