aPPR
helps you calculate approximate personalized pageranks from large
graphs, including those that can only be queried via an API. aPPR
additionally performs degree correction and regularization, allowing you
to recover blocks from stochastic blockmodels.
To learn more about aPPR
you can:
You can install the development version from GitHub with:
# install.packages("devtools")
devtools::install_github("RoheLab/aPPR")
igraph
graphlibrary(aPPR)
library(igraph)
set.seed(27)
erdos_renyi_graph <- sample_gnp(n = 100, p = 0.5)
erdos_tracker <- appr(
erdos_renyi_graph, # the graph to work with
seeds = "5", # name of seed node (character)
epsilon = 0.0005 # desired approximation quality (see ?appr)
)
erdos_tracker
#> Personalized PageRank Approximator
#> ----------------------------------
#>
#> - number of seeds: 1
#> - visits so far: 5
#> - unique nodes visited so far: 1 out of maximum of Inf
#> - bad nodes so far: 0
#>
#> - teleportation constant (alpha): 0.15
#> - desired approximation error (epsilon): 5e-04
#> - achieved bound on approximation error: 0.000416297883029663
#> - current length of to-visit list: 0
#>
#> PPR table (see $stats field):
#> # A tibble: 51 × 7
#> name r p in_degree out_degree degree_adjusted regularized
#> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 5 0.0205 0.147 50 50 0.00294 0.00147
#> 2 3 0.0167 0 51 51 0 0
#> 3 6 0.0167 0 59 59 0 0
#> 4 8 0.0167 0 41 41 0 0
#> 5 15 0.0167 0 46 46 0 0
#> 6 16 0.0167 0 52 52 0 0
#> 7 17 0.0167 0 48 48 0 0
#> 8 19 0.0167 0 54 54 0 0
#> 9 20 0.0167 0 51 51 0 0
#> 10 21 0.0167 0 55 55 0 0
#> # … with 41 more rows
You can access the Personalized PageRanks themselves via the stats
field of Tracker
objects.
erdos_tracker$stats
#> # A tibble: 51 × 7
#> name r p in_degree out_degree degree_adjusted regularized
#> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 5 0.0205 0.147 50 50 0.00294 0.00147
#> 2 3 0.0167 0 51 51 0 0
#> 3 6 0.0167 0 59 59 0 0
#> 4 8 0.0167 0 41 41 0 0
#> 5 15 0.0167 0 46 46 0 0
#> 6 16 0.0167 0 52 52 0 0
#> 7 17 0.0167 0 48 48 0 0
#> 8 19 0.0167 0 54 54 0 0
#> 9 20 0.0167 0 51 51 0 0
#> 10 21 0.0167 0 55 55 0 0
#> # … with 41 more rows
Sometimes you may wish to limit computation time by limiting the number of nodes to visit, which you can do as follows:
limited_visits_tracker <- appr(
erdos_renyi_graph,
seeds = "5",
epsilon = 1e-10,
max_visits = 20 # max unique nodes to visit during approximation
)
#> Warning: Maximum visits reached. Finishing aPPR calculation early.
limited_visits_tracker
#> Personalized PageRank Approximator
#> ----------------------------------
#>
#> - number of seeds: 1
#> - visits so far: 22
#> - unique nodes visited so far: 20 out of maximum of 20
#> - bad nodes so far: 0
#>
#> - teleportation constant (alpha): 0.15
#> - desired approximation error (epsilon): 1e-10
#> - achieved bound on approximation error: 0.00423832387327568
#> - current length of to-visit list: 100
#>
#> PPR table (see $stats field):
#> # A tibble: 100 × 7
#> name r p in_degree out_degree degree_adjusted regularized
#> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 5 0.212 0.118 50 50 0.00237 0.00119
#> 2 3 0.0140 0 51 51 0 0
#> 3 6 0.0140 0 59 59 0 0
#> 4 8 0.0140 0 41 41 0 0
#> 5 15 0.0136 0 46 46 0 0
#> 6 16 0.0138 0 52 52 0 0
#> 7 17 0.0138 0 48 48 0 0
#> 8 19 0.0137 0 54 54 0 0
#> 9 20 0.0135 0 51 51 0 0
#> 10 21 0.0138 0 55 55 0 0
#> # … with 90 more rows
rtweet
ftrevorc_ppr <- appr(
rtweet_graph(),
"ftrevorc",
epsilon = 1e-4,
max_visits = 5
)
#> Warning: Maximum visits reached. Finishing aPPR calculation early.
ftrevorc_ppr
#> Personalized PageRank Approximator
#> ----------------------------------
#>
#> - number of seeds: 1
#> - visits so far: 6
#> - unique nodes visited so far: 5 out of maximum of 5
#> - bad nodes so far: 10
#>
#> - teleportation constant (alpha): 0.15
#> - desired approximation error (epsilon): 1e-04
#> - achieved bound on approximation error: 0.00175980395529336
#> - current length of to-visit list: 5
#>
#> PPR table (see $stats field):
#> # A tibble: 210 × 7
#> name r p in_degree out_degree degree_adjusted regularized
#> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 7752257741314… 0.211 0.118 69 120 0.00172 5.50e-8
#> 2 17163639 0.00559 0 20033 1596 0 0
#> 3 9381208958721… 0.00559 0 372 179 0 0
#> 4 1359003756063… 0.00559 0 230 116 0 0
#> 5 76228303 0.00559 0 7253 2274 0 0
#> 6 1024298722828… 0.00559 0 382 829 0 0
#> 7 1264590946144… 0.00559 0 116 189 0 0
#> 8 1107711818997… 0.00559 0 3404 410 0 0
#> 9 1217315090 0.00559 0 20660 402 0 0
#> 10 1120701503763… 0.00559 0 354 243 0 0
#> # … with 200 more rows
aPPR
uses logger
for
displaying information to the user. By default, aPPR
is quite verbose.
You can control verbosity by loading logger
and setting the logging
threshold.
library(logger)
# hide basically all messages (not recommended)
log_threshold(FATAL, namespace = "aPPR")
appr(
erdos_renyi_graph, # the graph to work with
seeds = "5", # name of seed node (character)
epsilon = 0.0005 # desired approximation quality (see ?appr)
)
If you submit a bug report, please please please include a log file using the TRACE threshold. You can set up this kind of detailed logging via the following:
set.seed(528491) # be sure to set seed for bug reports
log_appender(
appender_file(
"/path/to/logfile.log" ## TODO: choose a path to log to
),
namespace = "aPPR"
)
log_threshold(TRACE, namespace = "aPPR")
tracker <- appr(
rtweet_graph(),
seed = c("hadleywickham", "gvanrossum"),
epsilon = 1e-6
)
People have a right to choose how public and discoverable their
information is. aPPR
will often lead you to accounts that interesting,
but also small and out of sight. Do not change the public profile or
attention towards these the people running these accounts, or any other
accounts, without their permission.
Chen, Fan, Yini Zhang, and Karl Rohe. “Targeted Sampling from Massive Block Model Graphs with Personalized PageRank.” Journal of the Royal Statistical Society: Series B (Statistical Methodology) 82, no. 1 (February 2020): 99–126. https://doi.org/10.1111/rssb.12349. arxiv
Andersen, Reid, Fan Chung, and Kevin Lang. “Local Graph Partitioning Using PageRank Vectors.” In 2006 47th Annual IEEE Symposium on Foundations of Computer Science (FOCS’06), 475–86. Berkeley, CA, USA: IEEE, 2006. https://doi.org/10.1109/FOCS.2006.44.