{"id":19856,"date":"2020-01-28T14:34:42","date_gmt":"2020-01-28T14:34:42","guid":{"rendered":"https:\/\/www.arimetrics.com\/glosario-digital\/sentiment-analysis"},"modified":"2026-09-15T07:57:53","modified_gmt":"2026-09-15T07:57:53","slug":"sentiment-analysis","status":"publish","type":"encyclopedia","link":"https:\/\/www.arimetrics.com\/en\/digital-glossary\/sentiment-analysis","title":{"rendered":"Sentiment Analysis"},"content":{"rendered":"<p><img decoding=\"async\" class=\"boxpad alignright wp-image-23051 size-full\" src=\"https:\/\/www.arimetrics.com\/wp-content\/uploads\/2021\/11\/sentiment-analysis.jpg\" alt=\"Sentiment Analysis\" width=\"300\" height=\"300\" style=\"margin-top:0;\" srcset=\"https:\/\/www.arimetrics.com\/wp-content\/uploads\/2021\/11\/sentiment-analysis.jpg 300w, https:\/\/www.arimetrics.com\/wp-content\/uploads\/2021\/11\/sentiment-analysis-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><strong>Definition:<\/strong><\/p>\n<p><strong>Sentiment analysis<\/strong>, also known as opinion mining, is a set of methods that identifies and classifies opinions, attitudes or evaluations expressed in text. It can be applied to reviews, surveys, customer service messages, social posts and other written sources.<\/p>\n<p>Its output commonly indicates positive, negative or neutral polarity, although it may also locate opinions about specific aspects or estimate emotions and degrees of intensity. <strong>These tasks are not equivalent<\/strong> and must be defined before the data is interpreted.<\/p>\n<p>The analysis may be performed manually or through rules, statistical models and <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/ai-artificial-intelligence\">artificial intelligence<\/a> techniques. <strong>Automated classification represents an estimate<\/strong>, not an unambiguous reading of each person&#8217;s intention.<\/p>\n\n<h2>How sentiment analysis works<\/h2>\n<p>The process begins by defining the question, source and unit to be classified. <strong>Analysing a complete document, a sentence or a specific aspect<\/strong>, such as price, delivery or support, does not produce the same result.<\/p>\n<p><strong>A common workflow includes these five stages:<\/strong><\/p>\n<ol>\n<li><strong>Collection:<\/strong> select relevant texts and retain the necessary information about language, date, channel and context.<\/li>\n<li><strong>Preparation:<\/strong> correct formats, detect the language and handle duplicates, noise or fragments that cannot be interpreted.<\/li>\n<li><strong>Representation:<\/strong> transform the text into features that a rule-based or <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/machine-learning\">machine learning<\/a> system can process.<\/li>\n<li><strong>Classification:<\/strong> assign a category, score or multiple labels according to the defined objective.<\/li>\n<li><strong>Evaluation:<\/strong> compare a sample against human annotations and review errors, coverage and changes in performance.<\/li>\n<\/ol>\n<p>Lexicon-based approaches associate words or expressions with a predefined orientation. Trained models learn patterns from labelled examples. <strong>Hybrid systems can combine both methods<\/strong> and add rules specific to a language or field.<\/p>\n<p>Aspect-based analysis attempts to link an evaluation to the element it concerns. A review may be positive about a camera and negative about its weight; <strong>a single label for the entire text would hide that difference<\/strong>.<\/p>\n<h2>Applications of sentiment analysis<\/h2>\n<p>The technique can summarise large sets of opinions and locate cases that require review. <strong>Its common applications include these five:<\/strong><\/p>\n<ul>\n<li><strong>Customer experience:<\/strong> group comments about products, deliveries, support or processes to identify recurring topics.<\/li>\n<li><strong>Brand monitoring:<\/strong> observe how expressed evaluations vary across defined channels and periods without confusing mentions with representativeness.<\/li>\n<li><strong>Product research:<\/strong> identify praised or criticised aspects and compare versions when the samples are equivalent.<\/li>\n<li><strong>Service and prioritisation:<\/strong> flag potentially urgent or negative messages for human review.<\/li>\n<li><strong>Market research:<\/strong> complement surveys, interviews or a <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/focus-group\">focus group<\/a> with opinions produced in other contexts.<\/li>\n<\/ul>\n<p><strong>Sentiment analysis describes what is expressed in the available data.<\/strong> It does not by itself demonstrate the satisfaction of an entire population, the success of a campaign or the cause of a commercial change.<\/p>\n<h2>Limitations and evaluation<\/h2>\n<p>Language depends on context. <strong>Negation, irony, sarcasm, comparisons and implicit references<\/strong> can reverse or qualify the apparent meaning of a sentence. Emojis, spelling errors and switches between languages create further difficulty.<\/p>\n<p>A model trained in one field may misinterpret another. Words such as <em>unpredictable<\/em> or <em>aggressive<\/em> can carry different evaluations when used about a film, an illness or an investment. <strong>The domain, language and period of the data must correspond to the intended use.<\/strong><\/p>\n<p>Quality is evaluated against a reference sample using metrics suited to the class distribution. Overall accuracy can be misleading when one category dominates the dataset; <strong>precision, recall, errors by class and disagreement between annotators should also be reviewed<\/strong>.<\/p>\n<p>The data may also contain biases or exclude certain groups. <strong>Human review remains necessary<\/strong> when a classification affects people, prioritises incidents or supports consequential decisions. Results should retain their context and limitations rather than being presented as an objective measure of public mood.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>What sentiment analysis is, how it classifies opinions, its applications and the limitations to consider when interpreting results.<\/p>\n","protected":false},"author":6,"featured_media":79641,"template":"","encyclopedia-tag":[1304],"class_list":["post-19856","encyclopedia","type-encyclopedia","status-publish","has-post-thumbnail","hentry","encyclopedia-tag-data-analysis"],"_links":{"self":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia\/19856","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia"}],"about":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/types\/encyclopedia"}],"author":[{"embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/users\/6"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/media\/79641"}],"wp:attachment":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/media?parent=19856"}],"wp:term":[{"taxonomy":"encyclopedia-tag","embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia-tag?post=19856"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}