```ruby
class Vote < ActiveRecord::Base
  belongs_to :user
  belongs_to :voteable, polymorphic: true
  
  validates :value, presence: true
  validates :user_id, presence: true
  validates :voteable_id, presence: true
  validates :voteable_type, presence: true
end
```

Edit validation in Vote model
user
```ruby
class Vote < ActiveRecord::Base
  belongs_to :user
  belongs_to :voteable, polymorphic: true

  validates :value, inclusion: { in: [true, false] }
  validates :value, exclusion: { in: [nil] }
  validates :user_id, presence: true
  validates :voteable_id, presence: true
  validates :voteable_type, presence: true
end
```
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