Selection of optimal lag length in ARDL Bound test

u.the method i know about optimal lag is below: may be it helps u
optimal lag length can be obtain in eviews..open quick menu ---> estimate var ---> write two of your variables in endogenous variable box(or all variables ) , writ constant name in exogenous variable box give lag interval like 1 2 . press ok
view menu-->lag structure --> lag length criteria --> enter lag value till 6 (i m not sure about this, according to your work ), select the lag which has maximmum stars like below ( lag 1 has max stars so this is the ptimal lag for the your variables)

Lag LogL LR FPE AIC SC HQ


0 -43.67185 NA 0.040479 2.468748 2 .555825 2.499447
1 101.1663 266.1891* 2.00e-05* -5.144126* -4.882896* -5.052030*
2 102.3907 2.117822 2.33e-05 -4.994092 -4.558708 -4.840599
3 103.3477 1.551911 2.76e-05 -4.829606 -4.220069 -4.614716

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