Appendix E. NASS comments

August 5, 2020

Appendix E: NASS Comments

Document Reviewed: SSB SFPS IV_5.18.20

(School Food Purchase Study IV (SFPS-IV) OMB Supporting Statement Part B)

Reviewed by: Dana Butler, Mathematical Statistician, Environmental and Economics Section

Comment:

In the last paragraph of the sub-section titled “Degree of accuracy needed for the purpose described in the justification”, a reference to the table values is stated as: Table B2 shows that for a mean percentage of 10 percent and a moderate/high amount of dispersion, the MDES is 14.6 percent, which in turn translates to an MDD of 1.46 percent.

However, for a mean percentage of 10 percent and a moderate/high amount of dispersion, table B2 shows MDES value= 14.01% and MDD value = 1.40%. See highlighted cells below:

Table B2. Statistical Precision and Minimum Detectable Differences

Population percent	Low/Moderate Std. Dev. (Std. Dev. = 25% of Mean)				Moderate/High Std. Dev. (Std. Dev. = 50% of Mean)
	50/50 split		75/25 split		50/50 split		75/25 split
	MDES	MDD	MDES	MDD	MDES	MDD	MDES	MDD
5	7.00%	0.35%	8.09%	0.40%	14.01%	0.70%	16.17%	0.81%
10	7.00%	0.70%	8.09%	0.81%	14.01%	1.40%	16.17%	1.62%
20	7.00%	1.40%	8.09%	1.62%	14.01%	2.80%	16.17%	3.23%