# d.ind.t.t: d from t for Between Subjects In MOTE: Effect Size and Confidence Interval Calculator

## Description

This function displays d for between subjects data and the non-central confidence interval estimating from the t-statistic.

## Usage

 `1` ```d.ind.t.t(t, n1, n2, a = 0.05) ```

## Arguments

 `t` t-test value `n1` sample size group one `n2` sample size group two `a` significance level

## Details

To calculate d, the t-statistic is multiplied by two then divided by the square root of the degrees of freedom.

d_s = 2 * t / sqrt(n1 + n2 - 2)

## Value

Provides the effect size (Cohen's d) with associated confidence intervals, degrees of freedom, t-statistic, and p-value.

 `d` effect size `dlow` lower level confidence interval of d value `dhigh` upper level confidence interval of d value `n1` sample size `n2` sample size `df` degrees of freedom (n1 - 1 + n2 - 1) `t` t-statistic `p` p-value `estimate` the d statistic and confidence interval in APA style for markdown printing `statistic` the t-statistic in APA for the t-test

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30``` ```#The following example is derived from the "indt_data" dataset, included #in the MOTE library. #A forensic psychologist conducted a study to examine whether #being hypnotized during recall affects how well a witness #can remember facts about an event. Eight participants #watched a short film of a mock robbery, after which #each participant was questioned about what he or she had #seen. The four participants in the experimental group #were questioned while they were hypnotized. The four #participants in the control group recieved the same #questioning without hypnosis. hyp = t.test(correctq ~ group, data = indt_data) #You can type in the numbers directly, or refer to the dataset, #as shown below. d.ind.t.t(t = -2.6599, n1 = 4, n2 = 4, a = .05) d.ind.t.t(-2.6599, 4, 4, .05) d.ind.t.t(hyp\$statistic, length(indt_data\$group[indt_data\$group == 1]), length(indt_data\$group[indt_data\$group == 2]), .05) #Contrary to the hypothesized result, the group that underwent hypnosis were #significantly less accurate while reporting facts than the control group #with a large effect size, t(6) = -2.66, p = .038, d_s = 2.17. ```

MOTE documentation built on May 2, 2019, 5:51 a.m.