Appendix 4
Wald test
Null hypothesis
F statistics
P value
No significant intercept
22.75
0.000
Author’s own
Appendix 5
Breusch–Pagan test
Null hypothesis
F statistics
P value
Constant variance
19.85
0.000
Author’s own
References
Abumhadi, N., Todorovska, E., Assenov, B., Tsonev, S., Vulcheva, D., Vulchev, D., et al. (2012).
Agricultural research in 21st century: Challenges facing the food security under the impacts of
climate change. Bulgarian Journal of Agricultural Science, 18(6), 801–818.
Ahmad, F. (2009). Food security in Pakistan. Pakistan Journal of Agriculture Sciences, 46(2),
83–89.
Ahmad, M., & Ahmad, A. (1998). An analysis of the sources of wheat output growth in the
“Barani” area of the Punjab. The Pakistan Development Review, 231–249.
Ahmad, M., Siftain, H., & Iqbal, M. (2014). Impact of climate change on wheat productivity in
Pakistan: A district level analysis. Climate change. Working Paper Series 1, Pakistan Institute
of Development Economics, Islamabad.
Ahmad, I., Ambreen, R., Sun, Z., & Deng, W. (2015). Winter-spring precipitation variability in
Pakistan. American Journal of Climate Change, 4(1), 115. doi:10.4236/ajcc.2015.41010
Asche, F., & Tveterås, R. (1999). Modeling production risk with a two-step procedure. Journal of
Agricultural and Resource Economics, 424–439.
Ashfaq, M., Zulfiqar, F., Sarwar, I., Quddus, M. A., & Baig, I. A. (2011). Impact of climate change
on wheat productivity in mixed cropping system of Punjab. Soil and Environment, 30(2), 110–
114.
Asmat, U., & Athar, H. (2015). Run-based multi-model interannual variability assessment of
precipitation and temperature over Pakistan using two IPCC AR4-based AOGCMs.
Theoretical and Applied Climatology, 1–16.
Asseng, S., Foster, I. A. N., & Turner, N. C. (2011). The impact of temperature variability on
wheat yields. Global Change Biology, 17(2), 997–1012.
Babar, S., & Amin, A. (2014). Climate change impact on Rabi and Kharif crops of
Khyber-Pakhtunkhwa. PUTAJ Humanities and Social Sciences, 21(1).
Barnwal, P., & Kotani, K. (2010). Impact of variation in climatic factors on crop yield: A case of
rice crop in Andhra Pradesh. India: Economics and Management Series. 17.
60
M.H. Abdullah et al.
Wald test
Null hypothesis
F statistics
P value
No significant intercept
22.75
0.000
Author’s own
Appendix 5
Breusch–Pagan test
Null hypothesis
F statistics
P value
Constant variance
19.85
0.000
Author’s own
References
Abumhadi, N., Todorovska, E., Assenov, B., Tsonev, S., Vulcheva, D., Vulchev, D., et al. (2012).
Agricultural research in 21st century: Challenges facing the food security under the impacts of
climate change. Bulgarian Journal of Agricultural Science, 18(6), 801–818.
Ahmad, F. (2009). Food security in Pakistan. Pakistan Journal of Agriculture Sciences, 46(2),
83–89.
Ahmad, M., & Ahmad, A. (1998). An analysis of the sources of wheat output growth in the
“Barani” area of the Punjab. The Pakistan Development Review, 231–249.
Ahmad, M., Siftain, H., & Iqbal, M. (2014). Impact of climate change on wheat productivity in
Pakistan: A district level analysis. Climate change. Working Paper Series 1, Pakistan Institute
of Development Economics, Islamabad.
Ahmad, I., Ambreen, R., Sun, Z., & Deng, W. (2015). Winter-spring precipitation variability in
Pakistan. American Journal of Climate Change, 4(1), 115. doi:10.4236/ajcc.2015.41010
Asche, F., & Tveterås, R. (1999). Modeling production risk with a two-step procedure. Journal of
Agricultural and Resource Economics, 424–439.
Ashfaq, M., Zulfiqar, F., Sarwar, I., Quddus, M. A., & Baig, I. A. (2011). Impact of climate change
on wheat productivity in mixed cropping system of Punjab. Soil and Environment, 30(2), 110–
114.
Asmat, U., & Athar, H. (2015). Run-based multi-model interannual variability assessment of
precipitation and temperature over Pakistan using two IPCC AR4-based AOGCMs.
Theoretical and Applied Climatology, 1–16.
Asseng, S., Foster, I. A. N., & Turner, N. C. (2011). The impact of temperature variability on
wheat yields. Global Change Biology, 17(2), 997–1012.
Babar, S., & Amin, A. (2014). Climate change impact on Rabi and Kharif crops of
Khyber-Pakhtunkhwa. PUTAJ Humanities and Social Sciences, 21(1).
Barnwal, P., & Kotani, K. (2010). Impact of variation in climatic factors on crop yield: A case of
rice crop in Andhra Pradesh. India: Economics and Management Series. 17.
60
M.H. Abdullah et al.