[Cookie Monster]

I am searching for the approximate value std dev for the NBA totals. Preferably, not the data for all the games, but instead for a subset of say closing line = 200-205 or any similar subset.

[Cookie Monster]

Hmm, as no one cared to answer, I had to dust off my stats memories from school.

From SBR tools I got that 1.5 point in totals (200-209.5) in average transform a +100 bet to a -114.7, or 53.42%. (I used 1.5 points as it is the maximum data in the screen; it is slightly more precise than 0.5 or 1 point). In the standard normal table I get that it is equivalent to 0.086 std devs. So 1 point is 0.086/1.5 = 0.0573 std devs. Thusly, the std dev is 1/0.0573 = 17.4

My last stats class was over 20 years ago, I hope I did not make any error. Could anyone check it?

[suicidekings]

Average total for each team and the standard deviation of the total is given in the second and third columns. At the bottom, the overall is shown as 18.3 for all teams so your 17.4 wasn't far off. The last four columns show average PF, PF stdev, average PA, and PA stdev for the NBA this season

NBA 2009/10 data

team total stdev PF stdev PA stdev
ATL 199 19.4 101.8 13.2 97.2 10.3
BOS 195 18.3 99.4 10.7 95.2 11.3
CHI 196 17.9 96.9 11.5 98.9 11.7
CHR 188 16.7 94.7 11.4 93.2 9.5
CLE 198 15.7 102.2 9.5 95.7 8.8
DAL 201 19.4 101.7 12.0 99.8 11.8
DEN 209 19.3 107.0 12.3 102.4 10.6
DET 194 16.2 94.2 9.4 99.4 10.9
GSW 221 20.6 108.8 13.2 112.5 12.3
HOU 205 18.8 102.1 11.0 102.5 11.9
IND 204 20.3 100.8 12.6 103.5 12.2
LAC 197 15.6 95.7 9.0 101.7 11.7
LAL 200 17.5 102.5 11.9 97.4 10.0
MEM 206 19.3 102.6 12.1 103.4 10.8
MIA 190 19.0 95.8 12.0 94.4 12.6
MIL 193 19.7 97.0 10.6 95.8 12.6
MIN 205 19.7 97.9 9.9 107.6 12.7
NJN 194 17.4 92.4 9.8 101.6 11.0
NOH 202 17.3 99.4 10.2 102.4 10.2
NYK 207 19.7 101.9 12.8 104.9 12.0
OKC 199 20.2 101.3 11.8 97.7 11.5
ORL 197 18.1 101.9 11.6 95.1 10.5
PHI 199 17.7 97.2 10.9 101.5 10.2
PHX 216 16.8 110.3 11.2 105.8 10.8
POR 193 17.4 98.2 10.2 94.7 10.7
SAC 204 15.8 99.9 10.1 103.9 9.0
SAN 197 19.3 101.3 12.1 95.9 10.8
TOR 209 18.4 103.5 9.3 105.6 13.8
UTA 203 19.7 104.4 12.8 98.8 10.8
WAS 197 17.5 96.0 11.1 100.8 9.5

AVG 201 18.3 100.3 11.1 100.3 11.1

Best I can do for now. Hope that helps.

[Cookie Monster]

Thanks very much. My math was right, I feel very intelligent (OK, it was an intro to stats problem easy for college freshmen).
I assumed that the big scoring teams would have a larger std dev, but Phoenix has one of the lowest. Oklahoma and Indiana are in the 20+, only below Golden State. Strange.

Once again, thanks.