28543
Though switching Siri 's functions to machine learning and algorithms , which dramatically cut its error rate , the company reportedly still failed to anticipate the popularity of Amazon 's Echo , which features the Alexa personal assistant .
 Amazon
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Amazon