Mean =
= Mean * n
SD =
= Var * (n-1) + ()2 / n
=(SD)2 * (n-1) + ()2 / n
n | Mean | =Mean * n | SD | =(SD)2 * (n-1) + ()2 / n | |
ATAI | 13 | 8.4 | 109.2 | 3.1 | 1032.6 |
NAO | 19 | 8.8 | 167.2 | 2.6 | 1593.04 |
MT | 18 | 6.2 | 111.6 | 2.9 | 834.89 |
Total | 50 | 388 | 3460.53 |
ANOVA
This is ANOVA - Single Factor. We first need to find the and . They are 'Total variance' and 'Variance in between the treatments' respectively.
We know
=
= 449.65
=
Note: We have to separately sum for all the treatment.
=69.68
379.97
Df (Bet) = k -1 ………..where k = no. of treatments
=2
Df (res) = N – k
=47
Test Stat = MSB / MSE
SS | df | MS (SS /df) | F-stat | |
Between | 69.68 | 2 | 34.84 | 4.3095 |
Error | 379.97 | 47 | 8.0845 | |
Total | 449.65 | 49 |
a)
Grand mean= Grand total / N
= 388 /50
= 7.76
MS-Treatments (MS between)
Ans: 34.84
b)
MS error = 8.0845
c)
SS | df | MS (SS /df) | F-stat | |
Between | 69.68 | 2 | 34.84 | 4.3095 |
Error | 379.97 | 47 | 8.0845 | |
Total | 449.65 | 49 |
p-value = P( > F-stat)
=P(F2,47 > 4.31)
p-value = 0.0191........................found using f-dist tables with df1 = 2 df2=47
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic...
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 9.2, 8.1 and 7.8 mm and standard deviations were 2.2, 3.3 and 3 mm for the ATAI,...
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 8.9, 7.4 and 7.8 mm and standard deviations were 1.5, 2.2 and 2.1 mm for the ATAI,...
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 9.2, 8.1 and 7.8 mm and standard deviations were 2.2, 3.3 and 3 mm for the ATAI,...
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 8.9, 7.4 and 7.8 mm and standard deviations were 1.5, 2.2 and 2.1 mm for the ATAI,...
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 9.2, 8.1 and 7.8 mm and standard deviations were 2.2, 3.3 and 3 mm for the ATAI,...
An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 8.4, 8.8 and 6.2 mm and standard deviations were 3.1, 2.6 and 2.9 mm for the ATAI,...
Reserve Problems Chapter 13 Section 2 Problem 2 An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical X-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 8.4, 8.8 and 6.2 mm and standard deviations were...
Reserve Problems Chapter 13 Section 2 Problem 2 An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 8.9, 7.4 and 7.8 mm and standard deviations were...
Reserve Problems Chapter 13 Section 2 Problem 2 An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 8.9, 7.4 and 7.8 mm and standard deviations were...
Reserve Problems Chapter 13 Section 2 Problem 2 An article in the American Journal of Emergency Medicine compared the ability to detect acute traumatic aortic injury (ATAI) on cervical x-ray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography (NAO) and 18 cases with multiple trauma (MT) without aortography. Measurements of the cervical soft-tissue width at the third cervical vertebrae generated the following results. Averages were 9.2, 8.1 and 7.8 mm and standard deviations were...