若有一组或两组不满足正态性分布,则需要看TheNPAR1WAYProcedure结果
Kolmogorov-SmirnovD0.147453Pr>D>0.1500
Cramer-vonMisesW-Sq0.07463Pr>W-Sq0.2317
Anderson-DarlingA-Sq0.452028Pr>A-Sq0.2399
Quantiles(Definition5)
QuantileEstimate
100%Max260.7
99%260.7
95%260.7
90%256.9
75%Q3251.8
50%Median231.1
25%Q1224.4
TheSASSystem08:
15Monday,November1,201411
TheTTESTProcedure
Statistics
LowerCLUpperCLLowerCLUpperCL
VariablegNMeanMeanMeanStdDevStdDevStdDevStdErr
xgroup112265.26271.87278.477.365210.39717.6533.0014
xgroup215227.24235.21243.1810.53614.39122.6963.7157
xDiff(1-2)26.4636.6646.8610.02912.78817.6534.9528
T-Tests方差齐性通过,看成组设计的T检验的equal;方差齐性检验没有通过则看unequal
VariableMethodVariancesDFtValuePr>|t|
xPooledEqual257.40<.0001小于0.05说明拒绝H0,H0指两组对应的总体均值是想等的,则两组对应的总体均值是不相等的。
此时再看样本的均值,group1271.9和group2235.2的均值,说明group1的好
xSatterthwaiteUnequal24.87.68<.0001
xCochranUnequal.7.68=0.0001
EqualityofVariances首先看这个
VariableMethodNumDFDenDFFValuePr>F
xFoldedF14自由度(15-1)111.920.2837大于0.05说明接受H0,方差齐性检验通过
TheSASSystem08:
15Monday,November1,201412
TheNPAR1WAYProcedure
WilcoxonScores(RankSums)forVariablex
ClassifiedbyVariableg
SumofExpectedStdDevMean
gNScoresUnderH0UnderH0Score
ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒ
group112255.0168.020.49390221.250(255/12)平均秩
group215123.0210.020.4939028.200
21.25大于8.2说明正常组大于患病组
WilcoxonTwo-SampleTest
Statistic(S)255.0000
NormalApproximation正太分布近似法
Z4.2208
One-SidedPr>Z<.0001onetwo为双侧概率类似于P值。
Two-SidedPr>|Z|<.0001
tApproximation
One-SidedPr>Z0.0001
Two-SidedPr>|Z|0.0003拒绝H0
ExactTest若四种方法所得的结果不一致,则看ExtractTest精确检验的结果。
One-SidedPr>=S4.027E-07
Two-SidedPr>=|S-Mean|8.053E-07拒绝H0
Zincludesacontinuitycorrectionof0.5.
Kruskal-WallisTest卡方
Chi-Square18.0214
DF1
Pr>Chi-Square<.0001拒绝H0
【练习4】从津丰小麦4个品系中分别随机抽取10株,测量其株高(cm),数据如下所示,问不同品系津丰小麦的平均株高之间的差别是否具有统计学意义?
若P<0.05,请作两两比较。
品系0-3-1:
63、65、64、65、61、68、65、65、63、64
品系0-3-2:
56、54、58、57、57、57、60、59、63、62
品系0-3-3:
61、61、67、62、62、60、67、66、63、65
品系0-3-4:
53、58、60、56、55、60、59、61、60、59
单因素多水平设计定量资料参数检验的前提条件与检验方法的选用
1、参数检验的前提条件:
①独立性、②正态性、③方差齐性。
2、检验方法的选用(假定资料满足独立性):
若资料经过某种变量变换后能满足正态性、方差齐性,则对变量变换后的数据可用方差分析。
调用过程:
univariate:
正态性检验(不用sort过程)
glm:
方差齐性检验及单因素k(k≥3)水平设计定量资料方差分析
npar1way:
非参数检验
【SAS程序】:
练习4
TheSASSystem08:
15Monday,November1,201413
TheUNIVARIATEProcedure
Variable:
x
GROUP=GROUP1
Moments
N10SumWeights10
Mean64.3SumObservations643
StdDeviation1.82878223Variance3.34444444
Skewness0.26432273Kurtosis1.7622322
UncorrectedSS41375CorrectedSS30.1
CoeffVariation2.84414033StdErrorMean0.57831172
BasicStatisticalMeasures
LocationVariability
Mean64.30000StdDeviation1.82878
Median64.50000Variance3.34444
Mode65.00000Range7.00000
InterquartileRange2.00000
TestsforLocation:
Mu0=0
Test-Statistic------pValue------
Student'stt111.1857Pr>|t|<.0001
SignM5Pr>=|M|0.0020
SignedRankS27.5Pr>=|S|0.0020
TestsforNormality
Test--Statistic--------pValue------
Shapiro-WilkW0.92112PrKolmogorov-SmirnovD0.250946Pr>D0.0740
Cramer-vonMisesW-Sq0.085141Pr>W-Sq0.1594
Anderson-DarlingA-Sq0.481933Pr>A-Sq0.1853
Quantiles(Definition5)
QuantileEstimate
100%Max68.0
99%68.0
95%68.0
90%66.5
75%Q365.0
50%Median64.5
25%Q163.0
TheSASSystem08:
15Monday,November1,201415
TheUNIVARIATEProcedure
Variable:
x
GROUP=GROUP2
Moments
N10SumWeights10
Mean58.3SumObservations583
StdDeviation2.75075747Variance7.56666667
Skewness0.40997918Kurtosis-0.2893516
UncorrectedSS34057CorrectedSS68.1
CoeffVariatio