> t. test(abcl, mu=4.0, alt="two. sided", conf=0.95) One Sample t-test data: abc1 t - -0.52475, df - 19, p-value = 0.6058 alternative hypothesis: true mean is not equal to 4 95 percent confidence interval: 2. 503416 4.896584 sample estimates: mean of x 3.7 > sd(abc1) [1] 2.556725 > cohensD(abc1, mu=4.0) Error in cohensD(abel, mu = 4) : could not find function "cohensD" > install . packages("Isr") trying URL 'https://cran. rstudio.com/bin/macosx/contriblsr_0.5.tgz' Content type 'application/x-gzip' length 215019 bytes (209 KB) downloaded 209 KB The downloaded binary packages are in /var/folders/q3/v6ncbqln77jbwksm3q30wfpc0000gn/T//RtmpIwzXSA/down1 paded_packages > library(lsr) > cohensD(abc1, mu=4.0) [1] 0. 1173376