The p hat is a symbol which stands for sample proportion. In equations, it is represented as a lower-case p with a small caret above it.Continue Reading
To understand what the p hat symbol represents and how it is used, the difference between a population and a sample must first be understood. In the study of statistics, the word "population" refers to the entire group that is being studied. A "sample," on the other hand, is only a part of that group. A sample is, ideally, representative of the entire group, meaning that a statistician can study the habits, behaviors and characteristics of that small group and then generalize the findings to the entire population. In statistics, a lower-case p without a caret above it stands for "population proportion." When a statistician calculates the population proportion, the entire group is being factored into the equation.
However, the p hat symbol is used to refer to an even smaller group: a proportion of the sample of the entire group. The p hat is often used when discussing the results of surveys. For example, a statistician asks a sample group of 500 adults if they like grape soda; 342 say yes, 100 say no and 58 have no opinion. The statistician is interested in which proportion like grape soda, so an equation will be formulated to find the p hat, or the proportion that answered "yes." The p hat will then be expressed as a percentage or a fraction of the sample group.Learn more about Statistics
According to the University of Connecticut, the criterion variable is the dependent variable, or Y hat, in a regression analysis. The criterion variable is the variable that the analysis predicts. The number given from the analysis fits into the regression line.Full Answer >
The coefficient of variation is used in statistics to measure distribution. It can be found from the ratio of the standard deviation over the mean of a set of numbers to calculate both probability and frequency. When it is used in finance, the mean is considered the expected return.Full Answer >
Misleading statistics are statistics that people use to defend bad or misleading arguments, often in an unfair or deceitful way. Bad sampling, whether due to bias or skewed sample sizes, can lead to a misleading statistic.Full Answer >
Sampling, in statistics, is a method of answering questions that deal with large numbers of individuals by selecting a smaller subset of the population for study. One of the most prevalent types of sampling is random sampling.Full Answer >