All Questions
10
questions
1
vote
0
answers
63
views
Different results of t test and biserial correlation?
I was wondering whether it is possible that a t test and a point biserial correlation can give different results (t-test shows groups differ significantly, correlation implies that variable does not ...
- 415
1
vote
1
answer
1k
views
Should paired data correlate when using paired samples t test?
I have repeated measurements from a usability study on 2 different interfaces (n=23). Since the difference between the measurements seems to be normally distributed I used paired samples t-test to ...
- 35
0
votes
1
answer
82
views
Limit of t-score as r->0 (for Pearson's correlation)
I have a very basic question. The t-score used in the significance test for the Pearson's correlation is given by:
$$
t = r \frac{\sqrt{(n-2)}}{\sqrt{(1-r^2)}},
$$
where $n$ is the sample size and $r$ ...
0
votes
0
answers
82
views
Self-contradictory asumption of normality? Nonparametric point-biseral correltion coeffiicent? t-test or Mann-Whitney U?
A. I know from the net that for a design with one binary variable and a second variable that is continuous but is NOT normally distributed, I can use BOTH the point-biserial correlation (which is ...
- 1,363
1
vote
2
answers
4k
views
How do I interpret the results of this SPSS paired samples t test?
Paired samples statistics (table 1): pretest score mean= 41.6667, post test score mean= 93.3333, N=3
Paired samples correlations (table 2) Correlations= -.277 , Sig.=.821
Paired samples Test (Table ...
- 11
1
vote
1
answer
136
views
Testing signficance of correlation
I have been trying to study on how to test significance for a correlation coefficient. So far I have seen that we calculate a value t and then either use p-value or critical value from the t-table to ...
- 13
0
votes
2
answers
398
views
Same Pearson correlation score
Given the metrics A and B, applied on the same data, resulting in (normalized) scores, I use Pearson correlation between them and the gold standard. I get almost exactly the same Pearson correlation ...
- 3
0
votes
1
answer
28
views
Comparing Self-Report Data to Binary results
I have two sets of data: DES scores (self-report) and whether dissociation was experienced during an experiment (yes or no). My sample size is 83 (71 no, 12 yes). I want to know if high DES scores are ...
- 183
5
votes
1
answer
240
views
Testing correlation and the t-statistic used in Simple Linear Regression
Given $H_0$ : $\rho=0$ and $H_A$ : $\rho\neq0$, we use the test statistic $t_{n-2}$ , which is $\frac{r\sqrt{n-2}}{\sqrt{1-r^2}}$. I have to show that $\frac{r\sqrt{n-2}}{\sqrt{1-r^2}}$ equals $\frac{\...
- 61
2
votes
2
answers
962
views
Student's test for correlation coef
In one of the articles I found such a statement:
The significance of the correlation coefficient was then verified
using Student's t test for independent variables
Is this incorrect or did I ...
- 1,478