In a research project on fair value accounting, we investigate whether larger firms are more likely to report fair value estimates in the balance sheet (estimated by variable fv_assets1). We define the firms with sales higher than sample median as large firms (variable hi_sale takes the value of 1) and others as small firms (variable hi_sale takes the value of 0). We hence perform in Stata a two-sample test (command ttest) and rank sum test (command ranksum) and obtain the output as follows.

. ttest fv_assetl, by(hi_sale) Two-sample t test with equal variances Group Obs Mean Std. Err. Std. Dev. [95% Conf. Interval ] 750 . 1333926 . 0569191 1.558795 . 0216526 . 2451327 752 192.2772 176.4985 4840. 052 -154. 2119 538. 7664 combined 1, 502 96.33324 88.37222 3424.922 -77. 0129 269. 6794 diff -192. 1439 176.7339 -538. 8156 154.5279 diff = mean(0) - mean(1) t= -1.0872 Ho: diff = 0 degrees of freedom = 1500 Ha: diff 0 Pr (T |t|) = 0.2771 Pr(T > t) = 0. 8614