ttest sysbp120 Onesample t test Variable Obs Mean
. ttest sysbp=120 One-sample t test ---------------------------------------Variable | Obs Mean Std. Err. Std. Dev. [95% Conf. Interval] -----+----------------------------------sysbp | 9 140 4. 082483 12. 24745 130. 5858 149. 4142 ---------------------------------------Degrees of freedom: 8 Ho: mean(sysbp) = 120 Ha: mean < 120 t = 4. 8990 P < t = 0. 9994 Ha: mean ~= 120 t = 4. 8990 P > |t| = 0. 0012 Ha: mean > 120 t = 4. 8990 P > t = 0. 0006 4. หาคา P-value เปดตาราง T=4. 8990 ; df=9 -1 ; p-value = ? 5. ตดสนใจและสรปผล ����� sys. BP �������� 40 �� �� bmi 20 -25 ������� 120 mm. Hg �������� 95% ci ������ 130. 59 -149. 41 mm. Hg
����� sysbp ������ bmi 20 -25 ����� 120 ������ 136 151 130 133 159 165 135 140. swilk sysbp Shapiro-Wilk W test for normal data Variable | Obs W V z Prob>z -------+------------------------sysbp | 10 0. 83031 2. 615 1. 828 0. 03375
xi yi di rank T- T+ 136 120 16 - 6 6 - 151 120 31 - 8 8 - 131 120 11 - 2 2 - 130 120 10 - 1 1 - 133 120 13 - 3 3 - 159 120 39 - 9 9 - 165 120 45 - 10 - 135 120 15 - 4. 5 - 135 120 15 - 4. 5 - 140 120 20 - 7 7 - T- = 55, T+ = 0 T=minimum(55, 0) = 0
3. เลอกวธการทางสถตและคำนวณคาสถต . signrank sysbp=120 Wilcoxon signed-rank test sign | obs sum ranks -----------------+------positive | 10 55 negative | 0 0 zero | 0 0 -----------------+------all | 10 55 unadjusted variance 96. 25 adjustment for ties -0. 13 adjustment for zeros 0. 00 ----- adjusted variance 96. 13 Ho: sysbp = 120 z = 2. 805 Prob > |z| = 0. 0050 expected 27. 5 0 55
. signrank sysbp=120 Wilcoxon signed-rank test sign | obs sum ranks -----------------+------positive | 10 55 negative | 0 0 zero | 0 0 -----------------+------all | 10 55 unadjusted variance 96. 25 adjustment for ties -0. 13 adjustment for zeros 0. 00 ----- adjusted variance 96. 13 Ho: sysbp = 120 z = Prob > |z| = expected 27. 5 0 55 2. 805 0. 0050 ���� ��� ������� 40 �� ���������� 120 mm. Hg ���
���� (Assumption) -�������� Assumption ��� Wilcoxon Rank ���� Mann-Whitney Test
3. เลอกวธการทางสถตและคำนวณคาสถต. sdtest chol , by(gr) Variance ratio test ---------------------------------------Group | Obs Mean Std. Err. Std. Dev. [95% Conf. Interval] -----+----------------------------------0 | 5 330. 8275 31. 50519 70. 44776 243. 3551 418. 3 1 | 5 195. 6296 18. 15616 40. 5984 145. 22 246. 0392 -----+----------------------------------combined | 10 263. 2285 28. 31189 89. 53005 199. 1826 327. 2745 ---------------------------------------Ho: sd(0) = sd(1) F(4, 4) observed = F_obs = F(4, 4) lower tail = F_L = 1/F_obs = F(4, 4) upper tail = F_U = F_obs = Ha: sd(0) < sd(1) P < F_obs = 0. 8445 Ha: sd(0) ~= sd(1) P < F_L + P > F_U = 0. 3110 3. 011 0. 332 3. 011 Ha: sd(0) > sd(1) P > F_obs = 0. 1555
. ttest chol, by(gr( Two-sample t test with equal variances ---------------------------------------Group | Obs Mean Std. Err. Std. Dev. [95% Conf. Interval[ ----------------------------------+----418. 4205 243. 1795 70. 56699 31. 55852 330. 8 5 | 0 245. 7961 145. 4039 40. 42648 18. 07927 195. 6 5 | 1 ----------------------------------+----combined | 10 263. 2 28. 31443 89. 53807 199. 1483 327. 2517 ----------------------------------+----diff | 135. 2 36. 37032 51. 3299 219. 0701 ---------------------------------------Degrees of freedom: 8 Ho: mean(0) - mean(1) = diff = 0 Ha: diff < 0 t = 3. 7173 P < t = 0. 9971 Ha: diff != 0 t = 3. 7173 P > |t| = 0. 0059 Ha: diff > 0 t = 3. 7173 P > t = 0. 0029
���� (Assumption) -������ di ������� Assumption ��� Wilcoxon match pair sign
3. ��������. swilk d Shapiro-Wilk W test for normal data Variable | Obs W V z Prob>z -------+------------------------d | 5 0. 95382 0. 545 -0. 721 0. 76445 . su d Variable | Obs Mean Std. Dev. Min Max -------+--------------------------d | 5 -27. 6 21. 65179 -60 0
���� - ���� . ttest cho 1=cho 2 Paired t test ---------------------------------------Variable | Obs Mean Std. Err. ----------------------------------+----cho 1 | 5 324 6. 78233 cho 2 | 5 296. 4 15. 13142 ----------------------------------+----diff | 5 27. 6 9. 682975 --------------------------------------- Std. Dev. [95% Conf. Interval[ 15. 16575 33. 83489 305. 1692 254. 3884 342. 8308 338. 4116 21. 65179 . 7157522 54. 48425 Ho: mean(cho 1 - cho 2) = mean(diff) = 0 Ha: mean(diff) < 0 t = 2. 8504 P < t = 0. 9768 Ha: mean(diff) != 0 t = 2. 8504 P > |t| = 0. 0464 Ha: mean(diff) > 0 t = 2. 8504 P > t = 0. 0232
���� - ����. ttest cho 2=cho 1 Paired t test ---------------------------------------Variable | Obs Mean Std. Err. ----------------------------------+----cho 2 | 5 296. 4 15. 13142 cho 1 | 5 324 6. 78233 ----------------------------------+----diff | 5 -27. 6 9. 682975 --------------------------------------- Std. Dev. [95% Conf. Interval[ 33. 83489 15. 16575 254. 3884 305. 1692 338. 4116 342. 8308 21. 65179 -54. 48425 -. 7157522 Ho: mean(cho 2 - cho 1) = mean(diff) = 0 Ha: mean(diff) < 0 t = -2. 8504 P < t = 0. 0232 Ha: mean(diff) != 0 t = -2. 8504 P > |t| = 0. 0464 Ha: mean(diff) > 0 t = -2. 8504 P > t = 0. 9768
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