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I am currently try to get information from the correlogram of residuals in eviews from a certain equation; I am supposed to understand if residuals are white noise or not and to adfirm that they are white noise, the p-values should be all greater than 0.05.

Anyway, there are some p-values which are missing; it's not that they are 0, they are not present at all! What does this mean? enter image description here

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I think the reason why the p-values are not reported is because the Q-statistic is follows a Chi-squared distribution, where the d.f. = the number of lags (e.g. at lag 2, d.f. = 2). However, for the residuals calculated from an ARMA or ARIMA estimation, the d.f. should be adjusted for the number of ARMA terms. So I suppose the output above comes from an ARMA with 4 terms (e.g. ARMA(2,2), ARMA(3,1),...). Thus the d.f. at lags 1-4 is <=0 and thus a p-value cannot be computed. This is based on the eviews help article here: http://www.eviews.com/help/helpintro.html#page/content%2Fseries-Correlogram.html%23ww159896

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Don't know why Eviews does this (on R and Stata, those p-values are automatically computed, as one would expect). For lags 1 to 4, the AC's and PAC's are all within the 'error bars' implying that the p-values for those lags are all below 0.05.

Therefore, residuals are white noise (are more accurately, you can't reject the null hypothesis that they are).

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As EViews says: the test is adjusted for an arma with 4 lags. Then, it is correcting the Q-Statistics to report only the correlation in more than 4 lags.

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