Fig. 3
Source Authors’ own work. Notes: The blue line is the solid line while the red lines that bounded the blue line are the critical bounds at 0.5. Variables’ description is provided in Table 4
NARDL plots of cumulative sum of recursive residuals—CUSUM (a1–a6) and cumulative sum square of recursive residuals—CUSUMSQ (b1–b6) for Models 1–6.