P.Mean >>
Category >> Definitions (crated 2000-09-18). |

This page lists brief definitions of commonly used terms in statistics and research.

**2010**

P.Mean: What is a Generalized Estimating Equations model? (created 2010-08-19). Generalized Estimating Equations (GEE) are a model for your data that can account for dependence among some of your measurements due to repeated measures, cluster sampling, or a longitudinal data set. It represents an extension of the Generalized Linear Model (GLM). Like the GLM, the GEE model allows you to specify a link function and a mean variance relationship. With the appropriate choice of these two items, you can specify a wide variety of models.

P.Mean: What is a good surrogate measure for
socioeconomic status (created 2010-05-03). I received a question, indirectly, about what might be a good surrogate
measure for socioeconomic status (SES). That raises two questions, actually.
What is SES, and how can we tell if a surrogate is a good surrogate for SES.

**2009**

P.Mean: What is a normal probability plot? (created 2009-10-29). The normal probability plot, sometimes called the qq plot, is a graphical way of assessing whether a set of data looks like it might come from a standard bell shaped curve (normal distribution). To compute a normal probability plot, first sort your data, then compute evenly spaced percentiles from a normal distribution. Optionally, you can choose the normal distribution to have the same mean and standard deviation as your data, or you can save some time by using evenly spaced percentiles from a standard normal distribution. Finally, plot the evenly spaced percentiles versus the sorted data. A reasonably straight line indicates a distribution that is close to normal. A markedly curved line indicates a distribution that deviates from normality.

All of the material above this paragraph is licensed under a Creative Commons Attribution 3.0 United States License. This page was written by Steve Simon and was last modified on 2010-08-19. The material below this paragraph links to my old website, StATS. Although I wrote all of the material listed below, my ex-employer, Children's Mercy Hospital, has claimed copyright ownership of this material. The brief excerpts shown here are included under the fair use provisions of U.S. Copyright laws.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

- Definition: What is a beta level?
- Definition: What is a binomial distribution?
- Definition: What is a binomial mean?
- Definition: What is a binomial probability?
- Definition: What is block randomization?
- Definition: What is a boxplot?

- Definition: What is a case control design?
- Definition: What is categorical data?
- Definition: What is a cohort design?
- Definition: What is a common cause of variation?
- Definition: What is a conditional probability?
- Definition: What is a control chart?
- Definition: What is a convenience sample?
- Definition: What is a correlation? (Pearson correlation)

- Definition: What is a decision rule?
- Definition: Descriptive study
- Definition: Descriptive statistics
- Definition: What is a diagnostic test?
- Definition: Dependent variable

- Definition: Independence
- Definition: Inferential statistics
- Definition: Interval data
- Definition: What is the interquartile range?
- Definition: Independent variable

- Definition: Likelihood ratio
- Definition: Likelihood ratio (extra information)
- Definition: What is a longitudinal design?

- Definition: What is the mean? (sample mean/population mean)
- Definition: What is the median?
- Definition: What is the mode?
- Definition: What is a mosaic plot?

- Definition: Negative Predictive Value
- Definition: Nominal data
- Definition: Normal distribution
- Definition: Normal probabilities

- Definition: Parallel groups design
- Definition: Parameter
- Definition: Percentiles
- Definition: Phi coefficient
- Definition: What is the point biserial correlation?
- Definition: Poisson distribution
- Definition: Population
- Definition: Positive Predictive Value
- Definition: What is a purposive sample?
- Definition: P-value

- Definition: Sample
- Definition: Sensitivity
- Definition: Special cause of variation
- Definition: Specificity
- Definition: Standard error
- Definition: Standard deviation
- Definition: Statistic
- Definition: Stem and leaf diagram

- Definition: What is a T statistic?
- Definition: What is a Type I error?
- Definition: What is a Type II error?

The definitions are also arranged within specific topics:

- Category: Control charts
- Category: Descriptive statistics
- Category: Diagnostic testing
- Category: Graphical display
- Category: Hypothesis testing
- Category: Measuring agreement
- Category: Poisson regression
- Category: Quality control
- Category: Research designs

**What now?**

Browse other categories at this site

Browse through the most recent entries

This work is licensed under a Creative Commons Attribution 3.0 United States License. This page was written by Steve Simon and was last modified on 2010-08-19.