# Definitions for developers starting with letter P

**P value**definition What is the assumption of no effect or no difference (the null hypothesis), of obtaining a result equal to or more extreme than what was actually**PageRank**definition What is importance of something, typically to rank it in a list of search results. “PageRank works by counting the number and quality of links to a**Pandas**definition What is A Python library for data manipulation popular with data scientists. See also Python**perceptron**definition What is network is the perceptron, which approximates a single neuron with n binary inputs. It computes a weighted sum of its inputs and ‘fires’ if**Perl**definition What is in pre-Linux UNIX systems. Perl has always been popular for text processing, especially data cleanup and enhancement tasks. See also**pivot table**definition What is lists of data, without requiring you to write a single formula or copy a single cell. But the most notable feature of pivot tables is that**Poisson distribution**definition What is usually over a period of time or space, used to help predict the probability of an event. Like the binomial distribution, this is a**posterior distribution**definition What is See prior distribution**predictive analytics**definition What is events, typically to aid in business planning. This incorporates predictive modeling and other techniques. Machine learning might be**predictive modeling**definition What is The development of statistical models to predict future events. See also predictive analytics, model**principal component analysis**definition What is direction with the most variance and then determines that as the first principal component. This is very similar to how regression works in**prior distribution**definition What is the unknown quantity to be estimated has many plausible values modeled by what's called a prior distribution. Bayesian inference is**probability distribution**definition What is discrete random variable is a listing of all possible distinct outcomes and their probabilities of occurring. Because all possible outcomes**Python**definition What is 1994 that is popular with people doing data science. Python is noted for ease of use among beginners and great power when used by advanced

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Definition of Python, Probability Distribution, Prior Distribution, Principal Component Analysis, Predictive Modeling, Predictive Analytics, Posterior Distribution, Poisson description.

What is Python, Probability Distribution, Prior Distribution in web development.