Figure 1.
Figure 2.
The results of ADF tests and PP tests for air transport and GDP
| ADF test | World | USA | China | Japan | India | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| p-value | Lag | p-value | Lag | p-value | Lag | p-value | Lag | p-value | Lag | |
| GDP | 0.943 | 3 | 0.356 | 3 | 0.981 | 3 | 0.946 | 3 | 0.99 | 3 |
| GDP Diff1* | 0.015 | 3 | 0.055 | 3 | 0.631 | 3 | 0.045 | 3 | 0.052 | 3 |
| AIR | 0.353 | 3 | 0.637 | 3 | 0.725 | 3 | 0.769 | 3 | 0.717 | 3 |
| AIR Diff1 | 0.021 | 3 | 0.354 | 3 | 0.058 | 3 | 0.01 | 3 | 0.364 | 3 |
| PP test | World | USA | China | Japan | India | |||||
| GDP | 0.976 | 3 | 0.485 | 3 | 0.99 | 3 | 0.987 | 3 | 0.99 | 3 |
| GDP Diff1 | 0.01 | 3 | 0.01 | 3 | 0.01 | 3 | 0.01 | 3 | 0.01 | 3 |
| AIR | 0.250 | 3 | 0.633 | 3 | 0.849 | 3 | 0.340 | 3 | 0.492 | 3 |
| AIR Diff1 | 0.01 | 3 | 0.01 | 3 | 0.01 | 3 | 0.01 | 3 | 0.01 | 3 |
The results of ADF tests and PP tests for maritime transport and GDP
| ADF test | World | USA | China | Japan | India | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| p-value | Lag | p-value | Lag | p-value | Lag | p-value | Lag | p-value | Lag | |
| GDP | 0.362 | 2 | 0.494 | 2 | 0.022 | 2 | 0.323 | 2 | 0.620 | 2 |
| GDP Diff1 | 0.146 | 2 | 0.426 | 2 | 0.720 | 2 | 0.426 | 2 | 0.734 | 2 |
| Maritime | 0.850 | 2 | 0.735 | 2 | 0.444 | 2 | 0.541 | 2 | 0.99 | 2 |
| Ma. Diff1 | 0.020 | 2 | 0.574 | 2 | 0.077 | 2 | 0.032 | 2 | 0.429 | 2 |
| PP test | World | USA | China | Japan | India | |||||
| GDP | 0.075 | 2 | 0.388 | 2 | 0.924 | 2 | 0.41 | 2 | 0.655 | 2 |
| GDP Diff1 | 0.01 | 2 | 0.01 | 2 | 0.01 | 2 | 0.013 | 2 | 0.014 | 2 |
| Maritime | 0.466 | 2 | 0.592 | 2 | 0.332 | 2 | 0.553 | 2 | 0.897 | 2 |
| Ma. Diff1* | 0.033 | 2 | 0.027 | 2 | 0.01 | 2 | 0.014 | 2 | 0.082 | 2 |
The correlation coefficients for the first differences between air transport and GDP
| R | p-value | N | |
|---|---|---|---|
| World total | 0.679 | <0.001 | 45 |
| USA | 0.693 | <0.001 | 45 |
| China | 0.405 | <0.001 | 45 |
| Japan | –0.081 | <0.001 | 45 |
| India | 0.500 | <0.001 | 45 |
The results of Granger causality tests for the first differences between air transport and GDP
| Area/country | AIR to GDP | GDP to AIR | ||
|---|---|---|---|---|
| F-value | p-value | F-value | p-value | |
| World total | 0.08 | 0.778 | 4.841 | 0.030 |
| USA | 3.776 | 0.055 | 5.112 | 0.026 |
| China | 0.733 | 0.572 | 1.661 | 0.169 |
| Japan | 8.693 | 0.004 | 0.566 | 0.454 |
| India | 9.396 | 4.17E–06 | 3.634 | 0.009 |
Details about variables, measurements, and source of data
| Variables | Measurements | Source = World Bank Group URL |
|---|---|---|
| GDP | In constant US dollars (US$) | https://data.worldbank.org/indicator/NY.GDP.MKTP.KD |
| AIR | In a million-ton-kilometers | https://data.worldbank.org/indicator/IS.AIR.GOOD.MT.K1 |
| Maritime (SEA) | In TEU | https://data.worldbank.org/indicator/IS.SHP.GOOD.TU |
The correlation coefficients for the first differences of maritime transport and GDP
| R | p-value | N | |
|---|---|---|---|
| World Total | 0.746 | < 0.001 | 19 |
| USA | 0.869 | < 0.001 | 19 |
| China | 0.403 | 0.070 | 19 |
| Japan | 0.869 | < 0.001 | 19 |
The results of Granger causality test for the first differences between maritime transport and GDP
| Area/country | Maritime to GDP | GDP to maritime | ||
|---|---|---|---|---|
| F-value | p-value | F-value | p-value | |
| World total | 6.951 | <0.001 | 1.294 | 0.340 |
| China | 1.976 | 0.147 | 2.078 | 0.132 |
| Japan | 0.496 | 0.739 | 0.794 | 0.546 |
| India | 0.880 | 0.528 | 0.237 | 0.937 |
The correlation coefficient for the first difference between air transport and GDP_
| Country | R | p-value | N |
|---|---|---|---|
| Japan | 0.2142 | 0.1627 | 43 |
IRF between air and maritime traffic volume and GDP for world total
| Shock GDP to air | Shock air to GDP | Shock GDP to maritime | Shock maritime to GDP |
|---|---|---|---|