Trivariate1 - Some Statistical Aspects of Viticultural...

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Some Statistical Aspects of Viticultural Measurement ; True or False? Ordinary haphazard choice is sufficient to guarantee randomness; if false, what is gained by gathering data randomly and/or systematically? .
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Stratified Sampling has long been an Agricultural Tool 5.3 The following data show the stratification of all the farms and the average acres of corn (maize) per farm in each stratum. For a sample of 100 farms,compute the same sizes in each stratum under (a) proportional allocation, (b) optimum allocation. Compare the precisions of these methods with that of simple random sampling, p.111, Cochran, W. G., (1977), Sampling Methods , third edition , Wiley, New York. Number of Average Standard Farm Size Farms Corn Acres Deviation (acres) 0-40 394 5.4 8.3 41-80 461 16.3 13.3 81-120 391 24.3 15.1 121-160 334 34.5 19.8 161-200 169 42.1 24.5 201-240 113 50.1 26.0 241- 148 63.8 35.2 Benefits. .[in] stratified sampling. .saving considerable time. .” TODAY 1977
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The Idea that Underlies Stratified Sampling “And don’t waste your time canvassing the whole building, young man. We all think alike.”
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Program that Selects Random Rows and Vines By changing the value of m the user can determine a new starting value of the random number sequence warmup k rnd 1 ( ) k 1 m .. m 1002 rand 100 102 106 103 109 101 107 310 301 300 305 306 304 308 = rand 1 ⟨ ⟩ randc = rand 0 ⟨ ⟩ randr = randc j bcnum floor deltacol 1 + ( ) rnd 1 ( ) [ ] + = randr j brnum floor deltarow 1 + ( ) rnd 1 ( ) [ ] + = j 0 n 1 - = deltacol lcnum - = deltarow lrnum brnum - = Replace the value of lcnum by the last column number 310 = Replace the value of bcnum by the beginning column number = Replace the value of lrnum by the last row number lrnum 110 = Replace the value of brnum by the beginning row number brnum 100 = n 10 = Replace the value of n by the number of random values desired PROGRAM THAT SELECTS A RANDOM VINE ROW AND COLUMN
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Sample Procedure Details In the office: 1. Choose blocks and varieties to be sampled. 2. Generate data collection sheet using MSAccess template. This will: a. Use the randomly selected row/vine numbers generated for the cluster counts b. Record the directions used in the cluster counts c. Indicate which shoot should be sampled. One of each of the 5 Gaussian nodes, labeled A-E, will be randomly selected (without replacement) for each vine within each row (resulting in all nodes sampled for each row). [1] The shoot that should be sampled is the one nearest to the indicated node. d. Choose which cluster should be sampled. This is based on an equal probability of sampling clusters 1, 2, and 3; if 3 is chosen, either a 1 or 2 (with equal probability) is also chosen in case there are not 3 clusters on the selected shoot. e. Generate a unique ID number for each sample site. 3. Label plastic bags with block, row, and direction.
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This note was uploaded on 02/04/2011 for the course PB HLTH 140 taught by Professor Tarter during the Fall '10 term at Berkeley.

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Trivariate1 - Some Statistical Aspects of Viticultural...

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