Data for Example 7.11

Tensile

Format

A data frame/tibble with 72 observations on two variables

tensile

plastic bag tensile strength (pounds per square inch)

run

factor with run number (1 or 2)

References

Kitchens, L. J. (2003) Basic Statistics and Data Analysis. Pacific Grove, CA: Brooks/Cole, a division of Thomson Learning.

Examples


boxplot(tensile ~ run, data = Tensile, 
        col = c("purple", "cyan"))

t.test(tensile ~ run, data = Tensile)
#> 
#> 	Welch Two Sample t-test
#> 
#> data:  tensile by run
#> t = -3.4505, df = 64.136, p-value = 0.0009946
#> alternative hypothesis: true difference in means between group 1 and group 2 is not equal to 0
#> 95 percent confidence interval:
#>  -25.029593  -6.674665
#> sample estimates:
#> mean in group 1 mean in group 2 
#>        102.3346        118.1868 
#>