False positives and negatives in the Spanish passive analysis

This article gives an overview of the cases in which the Yoast SEO passive voice assessment for Spanish will yield incorrect results. We always strive for results that are as accurate as possible. However, because of the irregularities in human language, it will never be possible to get our analysis 100% right.

Below you find a list of cases in which our analysis will either incorrectly detect passive voice in sentences that aren’t really passive (false positives) or in which it will fail to detect passive voice in sentences that are actually passive (false negatives).

It’s not necessary to know about all of those cases to write a good text. Rather, this overview is intended to give you some clues in case you’re wondering why certain sentences are not correctly detected by the passive voice analysis.

Passive voice in Spanish

To help you understand the false positives and negatives, here is a quick explanation of how the passive voice assessment works. The passive voice assessor in Spanish looks for sentences containing a passive auxiliary and a past participle (a passive verb).

Passive auxiliaries are formed using a form of the verb ‘ser’. They are ‘helper verbs’ to the main passive verb.

Past participles are the main verbs of a passive form. They are verb forms such as ‘escrito’ or ‘perdido’.

False positives in Yoast SEO for Spanish

The passive voice assessment will incorrectly detect a passive voice in the following cases:

1. When a sentence has contains a passive auxiliary and a participle, but those words serve different functions in that particular sentence.

For example, in a sentence like “Ambos aeropuertos también son unidos por un servicio de helicópteros.”, the words ‘son’ and ‘unidos’ form a passive voice.

However, it can happen that these two words occur in a sentence together but with different functions:

“Mis vecinos son de los Estados Unidos.”

In this sentence, the word ‘unidos’ is part of the country name ‘los Estados Unidos’. ‘Son’ describes a property of the subject (‘mis vecinos’). Therefore, ‘son’ and ‘unidos’ do not belong together and cannot form a passive. However, the passive voice detector does not know this and incorrectly analyses the sentence as containing a passive.

Another examples of such false positive is the sentence below:

“Fue un videojuego para PC adaptado y expandido a partir de un episodio del mismo nombre.”

In this sentence, ‘adaptado’ is an adjective describing the video game, while ‘fue’ is a verb introducing the game. Therefore, they do not form a passive. Having said that, the sentence could be transformed into a passive one by moving ‘fue’ to an auxiliary position: “El videojuego fue adaptado y expandido a partir de un episodio del mismo nombre.”.

2. When a word that can be a passive auxiliary also has additional meanings.

For example, ‘fuera’ is a conjugated form of ‘ser’ and as such can be an auxiliary. But, the word can also mean ‘outside’. When it occurs after a word that can be a passive verb, the passive voice assessor will incorrectly mark it as a passive:

“2,5 millones de españoles han estado residiendo fuera del país y 15 millones han viajado al exterior.”

False negatives in Yoast SEO for Spanish

The passive voice assessment will fail to detect a passive voice if the participle is a rare verb. The assessment detects participles based on a list of ~3500 most frequent participles in Spanish. Therefore, if a sentence contains a less frequent participle, the assessment will not detect it. Please let us know if you think there’s a participle we should add, and we will gladly add it to our list.