# independent 2-group t-test t.test(y1,y2) # where y1 and y2 are numeric # paired t-test t.test(y1,y2,paired=TRUE) # where y1 & y2 are numeric # one sample t-test t.test(y,mu=3) # Ho: mu=3 You can use the var.equal = TRUE option to specify equal variances and a pooled variance estimate. You can use the alternative="less" or alternative="greater ...

Oct 10, 2020 · Pooled Variance Example Unfortunately, because the confidence interval contains zero, we cannot determine if there is a difference in population means, as they could be equal. This is because zero is the value specified in the null hypothesis (i.e., the null value of the parameter), which demonstrates that there is no statistically significant ...

The one-sample t test requires the following statistical assumptions: 1. Random and Independent sampling. 2. Data are from normally distributed populations. Note: The one-sample t test is generally considered robust against violation of this assumption once N > 30.

warranted. These days, we use Levene’s Test. This test is somewhat lacking in power, but isn’t as bad as the other options. Fortunately for us, Levene’s Test is automatically run whenever you ask SPSS to do an independent-samples t-test. In other words, you don’t have to ask for the test, nor run it separately; it’s all automatic. Title: Microsoft Word - Two Sample t-Test and CIs 11.docx Author: Julian Parris Created Date: 2/9/2014 11:59:02 PM