Figure 7
The image contains two line graphs. The first graph, titled Autocorrelation Function (ACF), shows the autocorrelation values on the vertical axis ranging from -1.00 to 1.00 and the lag values on the horizontal axis ranging from 0 to 20. The data points are represented by blue dots connected by orange lines. A shaded area around the horizontal axis indicates the confidence interval. The second graph, titled Partial Autocorrelation Function (PACF), also shows partial autocorrelation values on the vertical axis ranging from -1.00 to 1.00 and the lag values on the horizontal axis ranging from 0 to 20. Similar to the first graph, the data points are represented by blue dots connected by orange lines, with a shaded area indicating the confidence interval. Both graphs illustrate the correlation of the time series with its own previous values, helping to identify the appropriate lag orders for modeling.ACF and PACF