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3. Production Sampling - Sample adequacy <br />In a similar vein, enclosed are data for production sampling <br />in 1992 for the Bear No. 1 and 2 mine sites. The combined <br />acreage of the sites is estimated at 2.45 acres. 155 production <br />samples (1/4 square meter plots) were collected to satisfy sample <br />adequacy (wet weight calculations indicated 150 samples required <br />- dry weight final data indicates I only needed 128). I have <br />enclosed two tables and two charts for your information. Table A <br />lists the production weights measured for each of the 155 plots. <br />Next to each sample are the cumulative average production weight <br />and sample variance as well as the associated sample adequacy <br />value. As you can see, average production decreases fairly <br />steadily to about 69 grams/plot and thereafter bounces around <br />between 66 and 72. This trend is more visually evident in the <br />enclosed graph of the production mean and how it changed with <br />increased sampling. Also note that at sample 22, the sample <br />adequacy was almost the same as the value at sample 155. In <br />between these two plot, its value bounced back and forth as shown <br />in the other enclosed graph. Table B demonstrates that while the <br />mean production over the first 77 and the last 78 samples are <br />different (70.2 versus 65.1), they are not significantly <br />different according to a t test comparison (calculated t value = <br />0.71). I guess all I'm saying in a very long-winded way is that <br />I feel like much of my sampling effort is aimed at meeting <br />adequacy and not aimed at determining the sample mean. Any new <br />advice you have is appreciated. <br />Please do not hesitate to contact me if I have not been <br />clear. Thanks for your attention to this letter. I hope your <br />toe is better so that you can make your triumphant return to the <br />basketball court. The season is still young. <br />Sincerely, <br />~~ <br />Matthew S. Hayes <br />