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BackgroundStandard setting is one of the most contentious topics in educational measurement. Commonly-used methods all have well reported limitations. To date, there is not conclusive evidence suggesting which standard setting method yields the highest validity.MethodsThe method described and piloted in this study asked expert judges to estimate the scores on a real MCQ examination that they consider indicated a clear pass, clear fail, and pass mark for the examination as a whole. The mean and SD of the judges responses to these estimates, Z scores and confidence intervals were used to derive the cut-score and the confidence in it.ResultsIn this example the new method’s cut-score was higher than the judges’ estimate. The method also yielded estimates of statistical error which determine the range of the acceptable cut-score and the estimated level of confidence one may have in the accuracy of that cut-score.ConclusionsThis new standard-setting method offers some advances, and possibly advantages, in that the decisions being asked of judges are based on firmer constructs, and it takes into account variation among judges.

p ‐Nitrobenzaldehyde reactant: 50 g. (0.36 mole) of p ‐nitrotoluene intermediate: p ‐nitrobenzaldiacetate product: p ‐nitrobenzoic acid product: p ‐bromobenzaldehyde intermediate: p ‐bromobenzaldiacetate product: p ‐nitrobenzaldehyde

NotesVol. 69 hydrate. This crude material contained 96% of the theoretical electropositive chlorine content. When it was distilled at 76-78°(10 mm.) this chlorine content was found to be 99% of theoretical. The distilled product melted at 4-4.5°cor., á204 1.544. Since the crude material is sufficiently pure for most purposes, the distillation, which is dangerous, ought to be avoided. z-Propyldichloramine was prepared by a modification of the above procedures. To an ice-cooled concentrated aqueous solution of 95 g. (1 mole) of ¿-propylamine hydrochloride (prepared in situ) was added slowly 2.25 moles of aqueous sodium hypochlorite (prepared by adding chlorine to cold 15% aqueous sodium hydroxide, 1.6 moles hypochlorous acid per liter). Simultaneously with this addition over two to three hours was added 6 N hydrochloric acid at such a rate that the acidity was maintained between pH 5.6 and 6.6. Brom cresol green and chlorphenol red papers can be used as criteria if the solution is allowed to creep into the paper so as to give an indicator zone ahead of the bleached zone.After two hours' subsequent stirring in the cold, the heavy oil was separated, washed once with 50 cc. cold water, twice with 50-cc. portions of 5% sodium thiosulfate, once with cold water, twice with cold 50% sulfuric acid and finally twice with cold water. The crude yield (97 g., 76% of theoretical) contained 94% of the theoretical electropositive chlorine content.Distillation at 41-43°( 15 mm.) resulted in 70% recovery of yellow oil (d2tl41.165; n23d 1.4572) which contained 99.8% of the calculated electropositive chlorine content.

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