Composite Movie Rating system

[warrentc3 40]

First crack at this... using powershell for now since it's my native language.

Attempting to create a composite movie rating leveraging the standard set of ratings sources, while adding weighting measures to various community ratings.

Definitely some more conditions and logic will be needed for scenarios where subsets of ratings sources are available, but the weighting math should hopefully mitigate a chunk of that.

Feedback welcome!

$moviename = "Monty Python and the Holy Grail"
$rtaudiencerating = 95
$rtaudiencecount  = 645107
$rtcriticrating   = 98
$rtcriticcount    = 82
$tmdbrating       = 7.8
$tmdbcount        = 5028
$traktrating      = 8.3
$traktcount       = 11089
$metacriticrating = 91
$imdbrating       = 8.2
$imdbcount        = 547137

$ratings = @{}
$null = $ratings.Add('tomatometerallaudience',@{'MaxValue'=100;'rating'=$rtaudiencerating;'weight'=10;'votecount'=$rtaudiencecount } )
$null = $ratings.Add('tomatometerallcritics',@{'MaxValue'=100;'rating'=$rtcriticrating;'weight'=10;'votecount'=$rtcriticcount} )
$null = $ratings.Add('themoviedb',@{'MaxValue'=10;'rating'=$tmdbrating;'weight'=20;'votecount'=$tmdbcount} )
$null = $ratings.Add('trakt',@{'MaxValue'=10;'rating'=$traktrating;'weight'=20;'votecount'=$traktcount} )
$null = $ratings.Add('metacritic',@{'MaxValue'=100;'rating'=$metacriticrating;'weight'=20;'votecount'=0} )
$null = $ratings.Add('imdb',@{'MaxValue'=10;'rating'=$imdbrating;'weight'=20;'votecount'=$imdbcount} )

$community = @{}
$totalcommunityvotes = $ratings['imdb'].votecount + $ratings['trakt'].votecount + $ratings['themoviedb'].votecount + $ratings['tomatometerallaudience'].votecount 
$imdbpercentvotes = [math]::Round( $ratings['imdb'].votecount / $totalcommunityvotes,3)
$traktpercentvotes =  [math]::Round( $ratings['trakt'].votecount / $totalcommunityvotes,3)
$tmdbpercentvotes =  [math]::Round( $ratings['themoviedb'].votecount / $totalcommunityvotes,3)
$rtpercentvotes =  [math]::Round( $ratings['tomatometerallaudience'].votecount / $totalcommunityvotes,3)
$communitysum = $imdbpercentvotes + $traktpercentvotes + $tmdbpercentvotes + $rtpercentvotes
if ( $communitysum -gt 1 ) { $rtpercentvotes = $rtpercentvotes - ($communitysum - 1) }
elseif ( $communitysum -lt 1 ) { $imdbpercentvotes = $imdbpercentvotes + (1 - $communitysum) }

$adjtraktcount = 1; 
if ( $traktpercentvotes -eq 0 -and $ratings['trakt'].votecount -ne 0 ) { $adjtraktcount = 100 }
elseif ( $traktpercentvotes -lt 0.002 ) { $adjtraktcount = 100 }
elseif ( $traktpercentvotes -lt 0.004 ) { $adjtraktcount = 80 }
elseif ( $traktpercentvotes -lt 0.006 ) { $adjtraktcount = 60 }
elseif ( $traktpercentvotes -lt 0.008 ) { $adjtraktcount = 50 }
elseif ( $traktpercentvotes -lt 0.010 ) { $adjtraktcount = 30 }
elseif ( $traktpercentvotes -lt 0.100 ) { $adjtraktcount = 10 }
$adjtmdbcount = 1; 
if ( $tmdbpercentvotes -eq 0 -and $ratings['themoviedb'].votecount -ne 0 ) { $adjtmdbcount = 100 }
elseif ( $tmdbpercentvotes -lt 0.002 ) { $adjtmdbcount = 100 }
elseif ( $tmdbpercentvotes -lt 0.004 ) { $adjtmdbcount = 80 }
elseif ( $tmdbpercentvotes -lt 0.006 ) { $adjtmdbcount = 60 }
elseif ( $tmdbpercentvotes -lt 0.008 ) { $adjtmdbcount = 50 }
elseif ( $tmdbpercentvotes -lt 0.010 ) { $adjtmdbcount = 30 }
elseif ( $tmdbpercentvotes -lt 0.100 ) { $adjtmdbcount = 10 }

$adjtotalcommunityvotes = $ratings['imdb'].votecount + ($ratings['trakt'].votecount*$adjtraktcount) + ($ratings['themoviedb'].votecount*$adjtmdbcount) + $ratings['tomatometerallaudience'].votecount 
$adjimdbpercentvotes = [math]::Round( $ratings['imdb'].votecount / $adjtotalcommunityvotes,3)
$adjtraktpercentvotes =  [math]::Round( ($ratings['trakt'].votecount * $adjtraktcount) / $adjtotalcommunityvotes,3)
$adjtmdbpercentvotes =  [math]::Round( ($ratings['themoviedb'].votecount * $adjtmdbcount) / $adjtotalcommunityvotes,3)
$adjrtpercentvotes =  [math]::Round( $ratings['tomatometerallaudience'].votecount / $adjtotalcommunityvotes,3)
$adjcommunitysum = $adjimdbpercentvotes + $adjtraktpercentvotes + $adjtmdbpercentvotes + $adjrtpercentvotes
if ( $adjcommunitysum -gt 1 ) { $adjrtpercentvotes = $adjrtpercentvotes - ($adjcommunitysum - 1) }
elseif ( $adjcommunitysum -lt 1 ) { $adjimdbpercentvotes = $adjimdbpercentvotes + (1 - $adjcommunitysum) }
$null = $community.Add('imdb',@{'votecount'=$ratings['imdb'].votecount;'percentage'=$imdbpercentvotes;'adjpercent'=$adjimdbpercentvotes } )
$null = $community.Add('trakt',@{'votecount'=$ratings['trakt'].votecount;'percentage'=$traktpercentvotes;'adjpercent'=$adjtraktpercentvotes } )
$null = $community.Add('themoviedb',@{'votecount'=$ratings['themoviedb'].votecount;'percentage'=$tmdbpercentvotes;'adjpercent'=$adjtmdbpercentvotes } )
$null = $community.Add('tomatometerallaudience',@{'votecount'=$ratings['tomatometerallaudience'].votecount;'percentage'=$rtpercentvotes;'adjpercent'=$adjrtpercentvotes } )

$communityweight = 70; 
if ( !$ratings.ContainsKey('metacritic') ) { $communityweight = $communityweight + 20 }
if ( !$ratings.ContainsKey('tomatometerallcritics') ){ $communityweight = $communityweight + 10 }
$scoring = @{}; $scoringtable = New-Object System.Collections.ArrayList
$ratings.GetEnumerator() | ForEach-Object { 
$current = $_;
$source = $current.Name
$sourcetype = $null; if ( $source -in ('tomatometerallcritics','metacritic') ) { $sourcetype = "Critic" } else { $sourcetype = "Community" } 
$sourcerating = $current.Value.rating
$sourcemax = $current.Value.MaxValue
if ( $sourcemax -eq 5 ) { $adjustedmax = $sourcemax*20; $adjustedrating = $sourcerating*20 } elseif ( $sourcemax -eq 10 ) { $adjustedmax = $sourcemax*10; $adjustedrating = $sourcerating*10 } else { $adjustedmax = $sourcemax; $adjustedrating = $sourcerating }
$sourcevotecount = $current.Value.votecount
$communitylookup = $null; $communitylookup = $community[$source]
$communityvotepercent = $communitylookup.percentage
$communityadjvotepercent = $communitylookup.adjpercent
$weighting = 0; if ( $sourcetype -eq "Community" ) { $weighting = $communityadjvotepercent * $communityweight }  else { $weighting = $current.Value.weight } 
$newcompositerating = ($adjustedrating * ($weighting/100 ) )
$null = $scoring.Add($source,@{'SourceType'=$sourcetype;'SourceVoteCount'=$sourcevotecount;'SourceRating'=$sourcerating;'SourceMax'=$sourcemax;'AdjustedRating'=$adjustedrating;'AdjustedMax'=$adjustedmax;'CommunityVotePrc'=$communityvotepercent;'AdjCommunityVotePrc'=$communityadjvotepercent; 'Weight'=$weighting; 'NewRating'= $newcompositerating } )
$null = $scoringtable.Add([pscustomobject]@{'Source' =$source;'SourceType'=$sourcetype;'SourceVoteCount'=$sourcevotecount;'SourceRating'=$sourcerating;'SourceMax'=$sourcemax;'AdjustedRating'=$adjustedrating;'AdjustedMax'=$adjustedmax;'CommunityVotePrc'=$communityvotepercent;'AdjCommunityVotePrc'=$communityadjvotepercent; 'Weight'=$weighting; 'NewRating'= $newcompositerating } )
}
#$highestweight = $scoringtable | Sort-Object Weight -Descending | Select-Object -First 1
if ( ($scoringtable.Weight | Measure-Object -Sum).Sum -gt 100.1 ) { Write-Warning "Weighting calculated over 100.1%"  }
elseif ( ($scoringtable.Weight | Measure-Object -Sum).Sum -lt 99.9 ) { Write-Warning "Weighting calculated under 99.9%"  }

$NewRating = [math]::Round( (($scoringtable.NewRating | Measure-Object -Sum).Sum/10),1) 
Write-Output "",""
Write-Output "Current movie is $($moviename)."
Write-Output "Rotten Tomatoes Critic rating is $($rtcriticrating) out of 100."
Write-Output "Rotten Tomatoes Community rating is $($rtaudiencerating) out of 100."
Write-Output "Metacritic rating is $($metacriticrating) out of 100."
Write-Output "Trakt community rating is $($traktrating) out of 10."
Write-Output "IMDB community rating is $($imdbrating) out of 10."
Write-Output "The MovieDB rating is $($tmdbrating) out of 10."
Write-Output "","New composite rating is $($NewRating) out of 10."

 

Edited March 7, 2023 by warrentc3
added comment

[Luke 37071]

Thanks for sharing.

[Riddler84 38]

Nice work. I like such aggregated ratings. Just for your interest, there's already a site, which does something like that. It's also including ratings from Letterboxd and RogerEbert.

Looking at your example, the site calculates a rating of 86 out of 100 for this movie. So it's pretty close.
https://mdblist.com/movie/tt0071853

[gbrock 2]

great idea!