Search found 341 matches
- Wed Jul 02, 2025 2:38 pm
- Forum: Module development
- Topic: Incorrect effect-size value in paired t-test
- Replies: 8
- Views: 40018
Re: Incorrect effect-size value in paired t-test
@Ravi The esci module appears to be calculating an effect size (and CI) for the difference between two means computed from paired samples, somehow taking the pairing into account, but NOT simply calculating the effect size (and CI) for difference scores.
- Wed Jul 02, 2025 1:55 am
- Forum: Statistics
- Topic: Chi square post hoc tests and correction for multiple testing
- Replies: 7
- Views: 6372
Re: Chi square post hoc tests and correction for multiple testing
@Andrzej_Andrew It is also common, after a chi square analysis, to want to know about proportions or ratios pertaining to subsets of the data. For example, you might want to know, is A/(A+B) significantly different from 0.5: (i) for Malay, (ii) for Indian, (iii) for Chinese? The overall chi square a...
- Thu Jun 26, 2025 4:14 pm
- Forum: jamovi development
- Topic: Adjusted p-values for multiple comparisons
- Replies: 5
- Views: 13472
Re: Adjusted p-values for multiple comparisons
I believe p.adjust is already used for post-hoc tests *within* particular jamovi analyses such as ANOVA. The difficulty is, how to take pieces of the output (i.e., individual p values) from various separate analyses (a t test here, a chi square there, and correlation from somewhere else) and make th...
- Fri Jun 20, 2025 11:00 pm
- Forum: Module development
- Topic: Incorrect effect-size value in paired t-test
- Replies: 8
- Views: 40018
Re: Incorrect effect-size value in paired t-test
In checking some examples in jamovi, it appears that the effect size for the paired samples t test is being computed correctly based on the standard deviation of the difference scores (and nothing to do with pooling). The esci module appears to be doing something else--not calculating the effect siz...
- Fri Jun 20, 2025 2:36 pm
- Forum: Module development
- Topic: Incorrect effect-size value in paired t-test
- Replies: 8
- Views: 40018
Re: Incorrect effect-size value in paired t-test
Hi. I think something may be wrong there. A paired t test is equivalent to a one-sample t test on difference scores. Therefore there is only one SD describing the sample of difference scores: There aren't multiple sample-SDs that would need to be pooled. So the concept of pooling shouldn't be applic...
- Sat Jun 14, 2025 1:19 am
- Forum: Help
- Topic: Change Decimal separator
- Replies: 6
- Views: 4507
Re: Change Decimal separator
Using jamovi's Rj module you can simply write some R code like: setwd("c:/Temp/") write.csv2(data, "ToothGrowth.csv") Note that write.csv2 writes semicolon-separated values and uses the comma as the decimal character. The resulting file opens properly in Excel when Excel has been...
- Fri Jun 13, 2025 3:33 am
- Forum: Help
- Topic: Change Decimal separator
- Replies: 6
- Views: 4507
Re: Change Decimal separator
Just an FYI. You can change Excel's settings so that is uses the dot as the decimal separator:
https://support.microsoft.com/en-us/off ... bb9837bd1e
https://support.microsoft.com/en-us/off ... bb9837bd1e
- Wed Mar 26, 2025 11:16 am
- Forum: Help
- Topic: Inconsistency in scale calculations
- Replies: 11
- Views: 116491
Re: Inconsistency in scale calculations
Hi. Thanks. To fix my example, there is only one item that is to be reverse-scored, and should be represented in my example as a column among several columns: 3243Untitled.png Yes, it ends up not mattering for correlation (reliability) computations because each column is ultimately converted to stan...
- Mon Mar 24, 2025 6:10 pm
- Forum: Help
- Topic: Inconsistency in scale calculations
- Replies: 11
- Views: 116491
Re: Inconsistency in scale calculations
Well, my suggestion was just the opposite: Always do the reverse scoring based on the theoretical not the actual range.
- Sun Mar 23, 2025 7:14 pm
- Forum: Help
- Topic: Inconsistency in scale calculations
- Replies: 11
- Views: 116491
Re: Inconsistency in scale calculations
RE "The choice of this adaptive method makes sense because the module cannot know the intended scale in advance." That's one way to look at it. But the way I see it, the only correct way to reverse-code is to base it on the theoretical, not the actual range of the data. For example, for -2...