any one help me get the standard deviation/ Average and extreme spread?

Deja vu · November 11, 2015, 05:41 PM

2025
2047
2069
2048
2017
2017(yes its 2 in a row)
2053
2067
2018
2034
2052
2050

These are 140 grain 357 magnums from a carbine loaded over Power Pro 300MP

p.s. tried to shoot 15 but got 3 errors.

FlyFish · November 11, 2015, 05:57 PM

The sd is 18.77 - that assumes you're interested (as you should be) in the sd of the entire population of velocities, of which your 12 data points represent a sample. Average deviation, which is what I think you mean by average spread is 16.01 - that's the average of the absolute values of the difference of each shot from the mean (you didn't ask, but the mean [average] is 2041.4). The extreme spread is simply the highest value (2069) minus the lowest value (2017) = 52.

wogpotter · November 12, 2015, 10:37 AM

Here you go. Calculated using Excel's functions which may differ very slightly from others.

Code:

#1	2025
#2	2047
#3	2069
#4	2048
#5	2017
#6	2017
#7	2053
#8	2067
#9	2018
#10	2034
#11	2052
#12	2050
===========
Std Dev	18.76872802
Average	2041.416667
Ex Spd	52

November 11, 2015, 05:41 PM	#1
Deja vu Senior Member Join Date: March 14, 2010 Location: Border of Idaho & Montana Posts: 2,584	any one help me get the standard deviation/ Average and extreme spread? 2025 2047 2069 2048 2017 2017(yes its 2 in a row) 2053 2067 2018 2034 2052 2050 These are 140 grain 357 magnums from a carbine loaded over Power Pro 300MP p.s. tried to shoot 15 but got 3 errors. __________________ Shot placement is everything! I would rather take a round of 50BMG to the foot than a 22short to the base of the skull. all 26 of my guns are 45/70 govt, 357 mag, 22 or 12 ga... I believe in keeping it simple. Wish my wife did as well... Last edited by Deja vu; November 11, 2015 at 05:56 PM.

November 11, 2015, 05:57 PM	#2
FlyFish Senior Member Join Date: January 20, 2009 Location: Overlooking the Baker River Valley Posts: 1,723	The sd is 18.77 - that assumes you're interested (as you should be) in the sd of the entire population of velocities, of which your 12 data points represent a sample. Average deviation, which is what I think you mean by average spread is 16.01 - that's the average of the absolute values of the difference of each shot from the mean (you didn't ask, but the mean [average] is 2041.4). The extreme spread is simply the highest value (2069) minus the lowest value (2017) = 52. __________________ NRA Benefactor Life Member NRA Certified Instructor: Rifle, Pistol, Shotgun, PPIH, Metallic & Shotgun Shell Reloading; RSO Pemigewasset Valley Fish & Game Club

November 12, 2015, 10:37 AM	#3
wogpotter Senior Member Join Date: September 27, 2004 Posts: 4,811	Here you go. Calculated using Excel's functions which may differ very slightly from others. Code: #1 2025 #2 2047 #3 2069 #4 2048 #5 2017 #6 2017 #7 2053 #8 2067 #9 2018 #10 2034 #11 2052 #12 2050 =========== Std Dev 18.76872802 Average 2041.416667 Ex Spd 52 __________________ Allan Quatermain: “Automatic rifles. Who in God's name has automatic rifles”? Elderly Hunter: “That's dashed unsporting. Probably Belgium.”