
Autocorrelation function (ACF) - Minitab
The autocorrelation function is a measure of the correlation between observations of a time series that are separated by k time units (y t and y t–k).
Methods and formulas for Autocorrelation - Minitab
The graphs for the autocorrelation function (ACF) of the ARIMA residuals include lines that represent the significance limits. Values that extend beyond the significance limits are …
Overview for Autocorrelation - Minitab
Use Autocorrelation to calculate and plot the correlation between observations of a time series. View the autocorrelation function plot to guide your choice of terms to include in an ARIMA …
Example of Autocorrelation - Minitab
The manager uses the autocorrelation function to determine which terms to include in an ARIMA model.
Data considerations for Autocorrelation - Minitab
Collect enough data so that you can fully assess trends or patterns in the data. Minitab displays correlations for only the first n/4 lags. So if you have monthly data, you'll need a large sample …
Enter your data for Autocorrelation - Minitab
Stat > Time Series > Autocorrelation. In Series, enter a column of numeric data that were collected at regular intervals and recorded in time order.
Methods and formulas for Partial Autocorrelation - Minitab
The partial autocorrelation function (PACF) is calculated from a recursive algorithm.
Guidelines for testing the autocorrelation or cross correlation
Guidelines for testing autocorrelation. A guideline based on large-sample normal approximation is often used to decide whether a specific sample autocorrelation is within sampling error of zero. …
Test for autocorrelation by using the Durbin-Watson statistic
The Durbin-Watson statistic tests for the presence of autocorrelation in the errors of a regression model. Autocorrelation means that the errors of adjacent observations are correlated.
Interpret the partial autocorrelation function (PACF) - Minitab
The partial autocorrelation function is a measure of the correlation between observations of a time series that are separated by k time units (y t and y t–k), after adjusting for the presence of all …