Predicting Board Game Collections

aboardgamebarrage’s Collection

Author

Phil Henrickson

Published

10/31/24

About

This report details the results of training and evaluating a classification model for predicting games for a user’s boardgame collection.

Note

To view games predicted by the model, go to Section 5.

Collection

The data in this project comes from BoardGameGeek.com. The data used is at the game level, where an individual observation contains features about a game, such as its publisher, categories, and playing time, among many others.

I train a classification model at the user level to learn the relationship between game features and games that a user owns - what predicts a user’s collection?

username status games
aboardgamebarrage ever_owned 456
aboardgamebarrage own 236
aboardgamebarrage rated 303

I evaluate the model’s performance on a training set of historical games via resampling, then validate the model’s performance on a set aside set of newer relases. I then refit the model on the training and validation in order and predict upcoming releases in order to find new games that the user is most likely to add to their collection.

username years type Own
no yes
aboardgamebarrage -3500-2020 train 24339 179
aboardgamebarrage 2021-2022 valid 9867 30
aboardgamebarrage 2023-2028 test 9072 27

Types of Games

What types of game does the user own? The following plot displays the most frequent publishers, mechanics, designers, artists, etc that appear in a user’s collection.

Show the code
collection |>
        filter(own == 1) |>
        collection_by_category(
                games = games_raw
        ) |>
        plot_collection_by_category()+
        ylab("feature")

The following plot shows the years in which games in the user’s collection were published. This can usually indicate when someone first entered the hobby.

Games in Collection

What games does the user currently have in their collection? The following table can be used to examine games the user owns, along with some helpful information for selecting the right game for a game night!

Use the filters above the table to sort/filter based on information about the game, such as year published, recommended player counts, or playing time.

Show the code
collection |>
        filter(own == 1) |>
        prep_collection_datatable(
                games = games_raw
        ) |>
        filter(!is.na(image)) |>
        collection_datatable()

Modeling

I’ll now the examine predictive models trained on the user’s collection.

For an individual user, I train a predictive model on their collection in order to predict whether a user owns a game. The outcome, in this case, is binary: does the user have a game listed in their collection or not? This is the setting for training a classification model, where the model aims to learn the probability that a user will add a game to their collection based on its observable features.

How does a model learn what a user is likely to own? The training process is a matter of examining historical games and finding patterns that exist between game features (designers, mechanics, playing time, etc) and games in the user’s collection.

I make use of many potential features for games, the vast majority of which are dummies indicating the presence or absence of the presence or absence of things such as a publisher/artist/designer. The “standard” BGG features for every game contain information that is typically listed on the box its playing time, player counts, or its recommended minimum age.

Note

I train models to predict whether a user owns a game based only on information that could be observed about the game at its release: playing time, player count, mechanics, categories, genres, and selected designers, artists, and publishers. I do not make use of BGG community information, such as its average rating, weight, or number of user ratings. This is to ensure the model can predict newly released games without relying on information from the BGG community.

What Predicts A Collection?

A predictive model gives us more than just predictions. We can also ask, what did the model learn from the data? What predicts the outcome? In the case of predicting a boardgame collection, what did the model find to be predictive of games a user has in their collection?

To answer this, I examine the coefficients from a model logistic regression with ridge regularization (which I will refer to as a penalized logistic regression).

Positive values indicate that a feature increases a user’s probability of owning/rating a game, while negative values indicate a feature decreases the probability. To be precise, the coefficients indicate the effect of a particular feature on the log-odds of a user owning a game.

The following visualization shows the path of each feature as it enters the model, with highly influential features tending to enter the model early with large positive or negative effects. The dotted line indicates the level of regularization that was selected during tuning.

Show the code
model_glmnet |> 
        pluck("wflow", 1) |>
        trace_plot.glmnet(max.overlaps = 30)+
        facet_wrap(~params$username)

Partial Effects

What are the effects of individual features?

Use the buttons below to examine the effects different types of predictors had in predicting the user’s collection.

Assessment

How well did the model do in predicting the user’s collection?

This section contains a variety of visualizations and metrics for assessing the performance of the model(s). If you’re not particularly interested in predictive modeling, skip down further to the predictions from the model.

The following displays the model’s performance in resampling on a training set, a validation set, and a holdout set of upcoming games.

Show the code
metrics |>
        mutate_if(is.numeric, round, 3) |>
        pivot_wider(
                names_from = c(".metric"),
                values_from = c(".estimate")) |>
        gt::gt() |>
        gt::sub_missing() |>
        gt_options()
username wflow_id type .estimator mn_log_loss roc_auc pr_auc
aboardgamebarrage glmnet resamples binary 0.035 0.887 0.091
aboardgamebarrage glmnet test binary 0.020 0.857 0.019
aboardgamebarrage glmnet valid binary 0.020 0.771 0.016

An easy way to visually examine the performance of classification model is to view a separation plot.

I plot the predicted probabilities from the model for every game (during resampling) from lowest to highest. I then overlay a blue line for any game that the user does own. A good classifier is one that is able to separate the blue (games owned by the user) from the white (games not owned by the user), with most of the blue occurring at the highest probabilities (left side of the chart).

Show the code
preds |>
        filter(type %in% c('resamples', 'valid')) |>
        plot_separation(outcome = params$outcome)

I can more formally assess how well each model did in resampling by looking at the area under the ROC curve (roc_auc). A perfect model would receive a score of 1, while a model that cannot predict the outcome will default to a score of 0.5. The extent to which something is a good score depends on the setting, but generally anything in the .8 to .9 range is very good while the .7 to .8 range is perfectly acceptable.

Show the code
preds |>
        nest(data = -c(username, wflow_id, type)) |>
        mutate(roc_curve = map(data, safely( ~ .x |> safe_roc_curve(truth = params$outcome)))) |>
        mutate(result = map(roc_curve, ~ .x |> pluck("result"))) |>
        select(username, wflow_id, type, result) |>
        unnest(result) |>
        plot_roc_curve()

Top Games in Training

What were the model’s top games in the training set?

Show the code
preds |>
        filter(type == 'resamples') |>
        prep_predictions_datatable(
                games = games, 
                outcome = params$outcome
        ) |>
        predictions_datatable(outcome = params$outcome,
                remove_description = T, 
                remove_image = T, 
                pagelength = 15)

Top Games in Validation

What were the model’s top games in the validation set?

Show the code
preds |>
        filter(type %in% c("valid")) |>
        prep_predictions_datatable(
                games = games,
                outcome = params$outcome
        ) |>
        predictions_datatable(
                outcome = params$outcome,
                remove_description = T, 
                remove_image = T, 
                pagelength = 15)

Top Games by Year

Displaying the model’s top games for individual years in recent years.

Show the code
preds |>
        filter(type %in% c('resamples', 'valid')) |>
        top_n_preds(
                games = games,
                outcome = params$outcome,
                top_n = 15,
                n_years = 15
        ) |>
        gt_top_n(collection = collection |> prep_collection())
Rank 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
1 Byzanz Jaipur Innovation Discworld: Ankh-Morpork The Resistance: Avalon Hemloch: Vault of Darkness Spyfall GEM Omen: Edge of the Aegean Dungeon of Mandom VIII Cosmic Encounter: 42nd Anniversary Edition Dune Nidavellir For Sale Autorama SPYBAM
2 Modern Art Card Game Hansa Teutonica Politico: The Fall of Caesar Omen: A Reign of War Archipelago Kobayakawa Maskmen 7 Wonders Duel Honshū Azul Mr. Face Omen: Fires in the East Cat in the box Oath Cat in the Box: Deluxe Edition
3 Ultimate Werewolf: Ultimate Edition Samurai: The Card Game Dominion: Big Box A Fake Artist Goes to New York Fleet Barrel Dice Chimera The Game + The Game on Fire Insider Merchants of Muziris Brass: Birmingham Detective: City of Angels Omen: Heir to the Dunes Kingdom Come Kongkang: The Wild Party
4 Seii Taishogun Greed Incorporated Earth Reborn Vanuatu Terra Mystica NFL Game Day Tricks & Deserts Keep Neolithic Breaking Bad: The Board Game Pax Emancipation One Night Ultimate Super Heroes Insider Black Import / Export: Definitive Edition Harry Potter: Kampf gegen die dunklen Mächte
5 Steel Driver Kuhhandel Master London Artus Libertalia Stone & Relic The Nile Ran Red Elysium Vampire Queen Cartouche Dynasties The Quacks of Quedlinburg One Night Ultimate Super Villains Mezo Kemet: Blood and Sand – Kickstarter Edition White Elephant: A Gift Exchange
6 Red November A Brief History of the World Time's Up! Family A Game of Thrones: The Board Game (Second Edition) Tooth & Nail: Factions A Study in Emerald Port Royal Hemloch: Midnight Edition Junk Art Jump Drive TOKYO METRO Marco Polo II: In the Service of the Khan Florenza: X Anniversary Edition The Diamond Swap Make the Difference
7 Time's Up! Edición Amarilla Telestrations Bhazum Takenoko Uchronia Skull King La Isla Watson & Holmes Hit Z Road Hemloch: Dark Promenade Decrypto SCOUT Hello Neighbor: The Secret Neighbor Party Game Moon Adventure A Game of Thrones: B'Twixt
8 Le Havre Steam De Vulgari Eloquentia Village Yedo Blueprints Power Grid Deluxe: Europe/North America Hordes of Grimoor Scythe Startups Coimbra Obscurio Guild Master Kemet: Blood and Sand 1877: Stockholm Tramways
9 Cosmic Encounter The Resistance Age of Industry Tournay Rex: Final Days of an Empire Habe fertig Irish Gauge Het Koninkrijk Dominion Welcome Back to the Dungeon The Game: Face to Face Rising Sun Century: A New World Sacred Rites Rome: Rising Empires Desamparados: Stalingrado
10 Kheops Imperial 2030 The Hobbit Mundus Novus The Great Zimbabwe Glass Road Pandemic: Contagion Soulfall One Night Ultimate Vampire Custom Heroes Underwater Cities Subtext The Cost Mint Bid Blood on the Clocktower
11 Strozzi Endeavor In a Grove The Castles of Burgundy Urbania Cinque Terre Deception: Murder in Hong Kong T.I.M.E Stories SYNOD Werewords Century: Eastern Wonders TOKYO COIN LAUNDRY Hues and Cues Facility 07 GridL
12 Córdoba Warhammer: Invasion Irondale Hemloch Keyflower Carcassonne: South Seas Orongo Grand Austria Hotel GearSeed One Night Ultimate Alien The Mind Ohanami The Red Cathedral Quest: Avalon Big Box Edition Hunch!
13 Toledo American Rails Hotel Samoa Friday Kemet Relic Imperial Settlers TROLL Codenames: Deep Undercover Sidereal Confluence Yellow & Yangtze Rurik: Dawn of Kiev Enigma: Beyond Code Ankh: Gods of Egypt Revive
14 Giants Pocket Rockets Mystery Express Dungeon Petz The Palaces of Carrara Bora Bora Onirim (Second Edition) One Night Ultimate Werewolf: Daybreak Game of Thrones: The Iron Throne A Game of Thrones: Catan – Brotherhood of the Watch Newton TOKYO GAME SHOW Ninja Catfoot and the Covert Action Bad Company The Middle Ages
15 Nefertiti Dominion: Intrigue Asara The City 卑怯なコウモリ (Cowardly Bat) Tash-Kalar: Arena of Legends Sons of Anarchy: Men of Mayhem Stockpile Mino Dice Claim The Binding of Isaac: Four Souls KOMBIO 13 Monsters Vitamors Conspiro Ultimate Werewolf: Extreme – Super Collector's Edition

Predictions

New and Upcoming Games

What were the model’s top predictions for new and upcoming board game releases?

Show the code
new_preds |>
        filter(type == 'upcoming') |>
        # imposing a minimum threshold to filter out games with no info
        filter(usersrated >= 1) |>
        # removing this goddamn boxing game that has every mechanic listed
        filter(game_id != 420629) |>
        prep_predictions_datatable(
                games = games_new,
                outcome = params$outcome
        ) |>
        predictions_datatable(outcome = params$outcome)

Older Games

What were the model’s top predictions for older games?