Why did it happen?

Diagnostic analytics is a form of advanced analytics that examines data or content to answer the question, “Why did it happen?” It is characterized by techniques such as drill-down, data discovery, data mining and correlations.Four Types of Data Analysis

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  Descriptive Analysis.
  
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  Diagnostic Analysis.
  
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  Predictive Analysis.
  
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  Prescriptive Analysis
  

Descriptive statistics is the term given to the analysis of data that helps describe, show or summarize data in a meaningful way such that, for example, patterns might emerge from the data.

Diagnostic analytics is a form of advanced analytics that examines data or content to answer the question, “Why did it happen?” It is characterized by techniques such as drill-down, data discovery, data mining and correlations.

Predictive analysis is the branch of advanced analytics which is used to make predictions about unknown future.c Predictive analytics uses many techniques from data mining, statics, modelling, machine learning and artifficial intelligence to analyze current data to make predictions abot future

Prescriptive analytics is a type of data analytics—the use of technology to help businesses make better decisions through the analysis of raw data. ... The opposite of prescriptive analytics is descriptive analytics, which examines decisions and outcomes after the fact