Ben Meissner

QNT/561

9/1/2014

Bonnie Merritt

Descriptive Statistics The microbrewery is trying to determine why profitability is inconsistent with sales. Over the past couple years the profits have decreased. The hypothesis is to determine if the mean net revenue for the first half of the year is less than or equal to the mean net revenue for the second half of the year. The variables used in the determination are sales (dependent variable) and cost of goods sold (COGS) (independent variable). The management consolidated a year of invoices. These invoices were segregated into two groups, first half of the year (Q1/Q2) and second half of the year (Q3/Q4). A sampling plan was established for each group. The sampling plan ensures 95% confidence with 5% error that mean sales and cost of goods sold is representative of the population. Invoices were randomly selected using a random number generator (see Appendix A). To evaluate this data, descriptive statistics and charting will be utilized.

Sales (Q1/Q2 and Q3/Q4) For both data sets the distributions are not normal (p < 0.05). The data is skewed to the right.

Q1/Q2 Sampling Results

Q3/Q4 Sampling Results

Central Tendency (Median)

299

347

Dispersion (Interquartile Range)

493 / 2 = +/- 247

511 / 2 = +/- 256

Count:

128

178

Min/Max:

-1,919 and 5,392

-2,015 and 11,115

Confidence Interval:

Not applicable, distribution is not normal

Not applicable, distribution is not normal

See descriptive statistics in Appendix B, and histograms in Appendix D.

Cost of Goods Sold (Q1/Q2 and Q3/Q4) For both data sets the distributions are not normal (p < 0.05). The data is skewed to the right.

Q1/Q2 Sampling Results

Q3/Q4 Sampling Results

Central Tendency (Median)

71

85

Dispersion (Interquartile Range)

127 / 2 = +/- 64

127 / 2 = +/- 64

Count:

128

178

Min/Max:

-465 and 1,343

-502 and 2,756

Confidence Interval:

Not applicable, distribution is not normal

Not applicable, distribution is not