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Now, how to figure out the standard deviation (equation 2) based on this table? Well, we‘ve
already done the top equation. Now we add all the numbers in the far right column together:
(3.24) +(7.94) +(3.24) +(1.44) + (27.04), which comes out to 42.90. Divide ( 5—1 = 4) that
by four which is always less than one from the total and it comes out to be 10.73. I used a
calculator to figure out the square root, which came out to be 3.27 (originally with a ton of
other numbers in the decimals place, but I narrowed it down to only the hundredth‘s place).
We had to do this for all the students so we calculated this 44 times.
This means that the standard deviation was 3.27 +/-. In English, it means that the numbers
can be described as close to the mean, not really ―deviating out of range‖ from it. A high
standard deviation would mean that the numbers are not very close to the mean. I did the
same thing with the data from the upper arm diastolic pressure, lower arm systolic pressure,
and lower arm diastolic pressure. The numbers came out to be 1.74, 5.29, and 5.68 respectively. So, the upper arm had standard deviations of 3.27 for systolic and 1.74 for the diastolic pressure. The lower arm had 5.29 for systolic and 5.68 for diastolic. Let‘s put the
measurements of diastolic pressure upper arm and lower arm together now, and do the
same with the systolic measurements. It came out to be 8.37 for the systolic, and 7.29 for
the diastolic. This means that the numbers were really far from the mean.
Conclusion:
After that equation, the class concluded that the differences between the brachium and antebrachium pressures are very different, so we can‘t really take the blood pressure of the
upper arm and assume that it is the same as the lower arm. If you want to take blood pressure readings on the wrist, we recommend that you use a machine designed for taking
blood pressures on lower arm (antebrachium).
Group members: In order of photo:
First row: Kenya, Jessica, Megan
Second Row: Allison, Michelle, Teresa, Kimmy, Madeline
Third Row: Ryan, Christopher
Not present: Xochial