years Geomagnetic surveys detect subsurface anomalies in the
Last updated: 1/19/2024
years Geomagnetic surveys detect subsurface anomalies in the earth s magnetic field These surveys have led to many significant archaeological discoveries After collecting data the next step is to begin a statistical study The following data measure magnetic susceptibility centimeter gram second x 10 6 on two of the main grids of the location The data for the x variable Grid E is given below The data for the y variable Grid H is given below a Compute Ex 2x 13 10 5 70 19 70 14 95 21 50 17 35 27 55 16 85 24 00 32 50 40 85 5 00 17 65 28 45 Compute Ex Ex Compute Ey y 11 95 15 15 21 20 17 40 27 40 10 25 14 80 48 80 25 50 25 85 57 70 34 45 38 70 41 10 31 15 Compute Ey Ey2 X s b Use the results of part a to compute the sample mean variance and standard deviation for x Round your answers to four decimal places S S USE SALT Use the results of part a to compute the sample mean variance and standard deviation for y Round your answers to four decimal places c Compute a 75 Chebyshev interval around the mean for x values Enter your answer in the form lower limit to upper limit Include the word to Round your numerical values to two decimal places Compute a 75 Chebyshev interval around the mean for y values Enter your answer in the form lower limit to upper limit Include the word to Round your numerical values to two decimal places Use the intervals to compare the magnetic susceptibility on the two grids Higher numbers indicate higher magnetic susceptibility However extreme values high or low could mean an anomaly and possible archaeological treasure O Grid H shows a wider 25 range of values Grid E shows a wider 75 range of values O Grid E shows a wider 25 range of values Grid H shows a wider 75 range of values d Compute the sample coefficient of variation in percent for x Round your answers to one decimal place Compute the sample coefficient of variation in percent for y Round your answers to one decimal place Use the CV s to compare the two grids Grid H demonstrates greater variability per expected signal Grid H demonstrates the same variability per expected signal as Grid E O Grid E demonstrates greater variability per expected signal If s represents variability in the signal magnetic susceptibility and x represents the expected level of the signal then s x can be thought of as a measure of the variability per unit of expected signal Remember a considerable variability in the signal above or below average might indicate buried artifacts Why in this case would a large CV be better or at least more exciting Explain A larger CV would indicate a possibility of more buried artifacts