1[2 {"id":"C1","text":"The OLS Okun coefficient over 1960Q1-2019Q4 (240 quarters) is about -0.26 pp of unemployment per percent of quarterly real GDP growth, with intercept 0.18 pp and R^2 0.41.","results_keys":["beta_hat","alpha_hat","r_squared","n_analysed","first_quarter","last_quarter"],"status":"supported","caveat":"Descriptive linear projection on current-vintage data; assumes a stable relation over the sample."},3 {"id":"C2","text":"The Newey-West (Bartlett, 4 lags) standard error is 0.036, about 1.8 times the iid OLS standard error of 0.020, consistent with residual autocorrelation of 0.39.","results_keys":["se_hac","se_iid","hac_lags","resid_lag1_autocorr"],"status":"supported","caveat":"Bandwidth from the Newey-West (1994) rule of thumb; no small-sample correction."},4 {"id":"C3","text":"The 95% HAC confidence interval for beta is [-0.326, -0.186]; beta is negative and significantly different from zero at the 5% level.","results_keys":["beta_ci_low","beta_ci_high","okun_negative_5pct","t_stat_hac","p_value_hac"],"status":"supported","caveat":"Normal critical values; finite-sample HAC size distortions possible but irrelevant at |t| about 7."},5 {"id":"C4","text":"The significance conclusion is robust to HAC bandwidths 0-12 and to the small-sample correction (SE range 0.029-0.037).","results_keys":["se_hac_by_lags","se_hac_small_sample_corrected"],"status":"supported","caveat":"Only Bartlett kernel examined."},6 {"id":"C5","text":"Mean quarterly real GDP growth over the sample is 0.754 percent.","results_keys":["mean_growth"],"status":"supported","caveat":""}7]8