ttest: Student's t-test to compare two means of objects of class... In intRvals: Analysis of Time-Ordered Event Data with Missed Observations

 ttest R Documentation

Student's t-test to compare two means of objects of class `intRvals`

Description

Performs one and two sample t-tests on objects of class `intRvals`

Usage

```ttest(
x,
y = NULL,
alternative = c("two.sided", "less", "greater"),
mu = 0,
var.equal = FALSE,
conf.level = 0.95
)
```

Arguments

 `x` an object of class `intRvals`, usually a result of a call to estinterval `y` an (optional) object of class `intRvals`, usually a result of a call to estinterval `alternative` a character string specifying the alternative hypothesis, must be one of "`two.sided`" (default), "`greater`" or "`less`". You can specify just the initial letter. `mu` a number indicating the true value of the mean (or difference in means if you are performing a two sample test). `var.equal` a logical variable indicating whether to treat the two variances as being equal. If TRUE then the pooled variance is used to estimate the variance otherwise the Welch (or Satterthwaite) approximation to the degrees of freedom is used. `conf.level` confidence level of the interval

Details

`alternative = "greater"` is the alternative that `x` has a larger mean than `y`.

If the input data are effectively constant (compared to the larger of the two means) an error is generated.

Value

A list with class "`htest`" containing the same components as in t.test

Examples

```data(goosedrop)
dr=estinterval(goosedrop\$interval)
# perform a one-sample t-test
ttest(dr,mu=200)  #> FALSE, true mean not equal to 200
# two sample t-test
data.beforeMay=goosedrop[goosedrop\$date<as.POSIXct('2013-05-01'),]
data.afterMay=goosedrop[goosedrop\$date>as.POSIXct('2013-05-01'),]
dr.beforeMay=estinterval(data.beforeMay\$interval)
dr.afterMay=estinterval(data.afterMay\$interval)
ttest(dr.beforeMay,dr.afterMay)

```

intRvals documentation built on May 3, 2022, 1:07 a.m.