Exercise
6:
Sampling and Shovel Test Pits. [Back]
[PDF version]
1. The file UNIFORM.DAT contains a set of integers that are uniformly
distributed between 0 and 30. Using Keith Kintigh's SAMPMEAN program
(copied into your working folder from the course web site), I want you
to take repeated samples from this population in order to observe first-hand
how individual samples differ from each other and from the original population.
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Construct histograms showing the sampling distribution of the mean for
samples of size 5, 10, 25, 50, and 100. In constructing each histogram,
use at least 100 trials.
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Compare these histograms with the underlying population and with each other,
and discuss the significance of your results.
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Now, using a sample size of 15, run at least 20 trials, and look at the
frequency distribution of each sample. Discuss what you see in these
samples, especially as compared to the underlying distribution.
Feel free to play with SAMPMEAN, and to try other sampling experiments
(no need to hand in the results unless you want to). Once you get
the hang of it, I think you'll find it both informative and fun.
[Note: You must run SAMPMEAN from within an MS-DOS window. Your results
can be printed by copying and pasting the output into your word processor.
To copy the output from the MS-DOS window, right-click.on the window, choose
“select all,” then paste into your word processor. Be sure to use a
fixed-pitch font, like Courier New.]
2. You have been asked to look for sites in a vegetated field
200 m long and 100 m wide. You have enough time and money to dig
either 200 shovel test pits (STPs) with a diameter of 0.50 m, or 40 1-by-1-m
squares. Using Kintigh's programs PLACESTP and STP (on the course
web site), please answer the following questions:
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Which is the better technique to use if you are looking for Mississippian
farmsteads? Assume that such farmsteads average about 25 m in diameter
and have an average artifact density of 20 per square meter.
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Which is the better technique to use if you are looking for Archaic lithic
scatters? Assume that such scatters average about 50 m in diameter
and have an average artifact density of 0.25 per square meter.
[Note: When specifying the input and output file names, be sure to include
the full path if the file is in a different folder than the program.
If the files are in the same folder as the program, then the file names
alone will be sufficient.]
Datasets and program files for this exercise (right-click to download):
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UNIFORM.dat (delete ".txt" suffix after downloading)
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SAMPMEAN.exe (for program documentation click
here)
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PLACESTP.exe (for program documentation click
here)
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STP.exe (for program documentation click here)
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