homnormal (version 0.1)

levene: Levene Test for Homogeniety

Description

Tests the homogeniety of variances for more than two normal groups.

Usage

levene(x1, x2, alfa = 0.05, table = TRUE, graph = "none")

Value

if table is TRUE, then it gives a detailed table, else it gives a vector of r value(r=1 when null hypothesis was rejected and r=0 when null hypothesis was accepted) p-value and test statistic value.

Arguments

x1

a numeric matrix containing the values of groups.

x2

numeric matrix containing the values of group numbers.

alfa

significance level of the test. Default number is 0.05.

table

a logical variable that indicates table will appear or not. Default is TRUE.

graph

box plot of groups of raw or centered data.

References

Levene, H. (1960). Robust tests for equality of variances, p 278–292. Contributions to probability and statistics: essays in honor of Harold Hotelling. Stanford University Press, Palo Alto, CA.

See Also

Brown_Forsythe, Cat_GG, Cat_LR, genp, slrt, bdai

Examples

    data(FH_data)
   x1=FH_data$SurvivalTime
   x2=FH_data$HospitalNo
   levene(x1,x2)
   readline(prompt = "Pause. Press  to continue...")
   levene(x1,x2,alfa=0.10)
   readline(prompt = "Pause. Press  to continue...")
    levene(x1,x2,alfa=0.10,table=FALSE)
    readline(prompt = "Pause. Press  to continue...")
    levene(x1,x2,alfa=0.10,table=FALSE,graph="raw")
    readline(prompt = "Pause. Press  to continue...")
# ---THIS VERSION IS ESPECIALLY USEFUL FOR COMPARISON STUDIES BY SIMULATION---
#    #first value of the vector is r value(r=1 when rejected and r=0 when accepted null hypothesis)
# second value of the vector is the p-value and third value is the tests statistic value