Statistics Definitions > What is Linear Discriminant Analysis? In statistics, pattern recognition and machine learning, linear discriminant analysis (LDA), also called canonical Variate Analysis (CVA), is a way to study differences between objects. This sorting method uses a linear combination…

## Subgroup Analysis

Experimental Design > Subgroup analysis is research that focuses on one or more subgroups of the main data set. It attempts to find and illustrate patterns within and between subgroups. It is widely used in medical research; the price tag…

## Quintile: Definition, Examples in Economics, Health

Statistics Definitions > A quintile is a 1/5th (20 percent) portion of the whole. In statistics, it’s a population or sample divided into five equal groups, according to values of a particular variable. It can also be used to refer…

## Lurking Variable: Simple Definition, Examples

Types of Variables > What is a Lurking Variable? A lurking variable is a variable that is unknown and not controlled for; It has an important, significant effect on the variables of interest. They are extraneous variables, but may make…

## Agglomerative Clustering

Hierarchical Clustering > What is Agglomerative Clustering? Agglomerative clustering (also called (Hierarchical Agglomerative Clustering, or HAC)) is a “bottom up” type of hierarchical clustering. In agglomerative clustering, each data point is defined as a cluster. Pairs of clusters are merged…

## Intention to Treat

RCTs > Intention to treat (ITT) analysis is a method of statistical analysis often used in medical research. In ITT analysis, a study participant is analyzed as belonging to whatever treatment group he/she was randomized into, whether or not the…

## Ljung Box Test: Definition

Autocorrelation > The Ljung (pronounced Young) Box test (sometimes called the modified Box-Pierce, or just the Box test) is a way to test for the absence of serial autocorrelation, up to a specified lag k. The test determines whether or…

## Excel PERCENTRANK Function, PERCENTILE & RANK

Excel for Statistics > How to use the Excel PERCENTILE function, PERCENTRANK function and RANK function Contents: PERCENTILE / PERCENTRANK RANK Excel PERCENTILE function and Excel PERCENTRANK function: Overview Watch the video or read the steps below: Update 09/02/2016: The…

## Frequency Domain: Definition

Statistics Definitions > Frequency domain analysis refers to analysis where a signal is studied with respect to frequency, rather than with respect to time. The data being studied is plotted with the frequency on the x axis and the amplitude…

## Curve Fitting

Trend Analysis > Curve fitting is the way we model or represent a data spread by assigning a ‘best fit‘ function (curve) along the entire range. Ideally, it will capture the trend in the data and allow us to make…