The **Full form** of ACF is **Auto-Correlation Function,** or ACF stands for **Auto-Correlation Function**, or the full name of given abbreviation is **Auto-Correlation Function**.

## Full forms of ACF

- Auto-Correlation Function
- Authentication Control Function
- Access Coordination Function
- Advanced Communications Facility
- Advanced Communications Function
- Adobe Photoshop Custom Filter
- Auto-correlation Function
- Anisotropic Conductive Film
- Auto- Correlation Function
- Actual Cubic Feet
- Advanced Computer Feasability
- Access Control Facility
- Airlift Clearance File
- Air Contingency Force

## ACF (Auto-Correlation Function)

Auto-Correlation Function is known as **ACF**, Autocorrelation, also known as **serial correlation**, is the correlation of a signal with a delayed copy of itself as a function of delay. Informally, it is the similarity between observations as a function of the time lag between them.

The analysis of autocorrelation is a mathematical tool for finding repeating patterns, such as the presence of a periodic signal obscured by noise, or identifying the missing fundamental frequency in a signal implied by its harmonic frequencies. It is often used in signal processing for analyzing functions or series of values, such as time domain signals.

- Different fields of study define autocorrelation differently, and not all of these definitions are equivalent. In some fields, the term is used interchangeably with autocovariance.
- Unit root processes, trend stationary processes, autoregressive processes, and moving average processes are specific forms of processes with autocorrelation.