Skip to main content
Polarity is measured on the normalized scale [-1, 1]. The method used here is rather naïve. It simply looks up each word in the text in a “polarity lexicon”, which assigns each emotionally charged word a numeric score. The individual scores are then simply averaged across the whole text. This will hence not account for contexts involving irony, sarcasm, or even simple negations.

Usage

The following examples show how the step can be used in a recipe.

Examples

  • Example 1
  • Example 2
  • Signature
To detect the sentiment for languages supported by default, use:
infer_sentiment(ds.text, ds.lang) -> (ds.sentiment)

Inputs & Outputs

The following are the inputs expected by the step and the outputs it produces. These are generally columns (ds.first_name), datasets (ds or ds[["first_name", "last_name"]]) or models (referenced by name e.g. "churn-clf").
text
column[text]
required
A text column to infer sentiment polarities for.
*lang
column[category]
An (optional) column identifying the languages of the corresponding texts. It is used to identify the correct model (spaCy) to use for each text. If the dataset doesn’t contain such a column yet, it can be created using the infer_language step. Ideally, languages should be expressed as two-letter ISO 639-1 language codes, such as “en”, “es” or “de” for English, Spanish or German respectively. We also detect fully spelled out names such as “english”, “German”, “allemande” etc., but it is not guaranteed that we will recognize all possible spellings correctly always, so ISO codes should be preferred.Alternatively, if all texts are in the same language, it can be identified with the language parameter instead.
sentiment
column[number]
required
A column containing the overall sentiment polarity for each input text.

Configuration

The following parameters can be used to configure the behaviour of the step by including them in a json object as the last “input” to the step, i.e. step(..., {"param": "value", ...}) -> (output).

Parameters

extended_language_support
boolean
default:"false"
Whether to enable support for additional languages. By default, Arabic (“ar”), Catalan (“ca”), Basque (“eu”), and Turkish (“tu”) are not enabled, since they’re supported only by a different class of language models (stanfordNLP’s Stanza) that is much slower than the rest. This parameter can be used to enable them.
min_language_freq
[number, integer]
default:"0.02"
Minimum number (or proportion) of texts to include a language in processing. Any texts in a language with fewer documents than these will be ignored. Can be useful to speed up processing when there is noise in the input languages, and when ignoring languages with a small number of documents only is acceptable. Values smaller than 1 will be interpreted as a proportion of all texts, and values greater than or equal to 1 as an absolute number of documents.
  • number
  • integer
{_}
number
number.Values must be in the following range:
0 < {_} < 1
language
[string, null]
The language of inputs texts. If all texts are in the same language, it can be specified here instead of passing it as an input column. The language will be used to identify the correct spaCy model to parse and analyze the texts. For allowed values, see the comment regarding the lang column above.
I