tValue

David Bourne david@boomer.org

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5 Aug 2023 v2.0.1 submitted for approval. Approved and available

Updated for iOS 16

29 Mar 2020 v2.0 submitted for approval. Approved, 30 Mar 2020 and available.

Updated using SwiftUI
Updated iOS 13.4
AND it seems to work with the new Apple M1 chipped MacBook!! Best in Portrait mode.

4 Nov 2018 v1.4 Submitted for approval. Approved, 5 Nov 18 and available.

Updated for iOS 12 and iPhones Xr, Xs, Xs Max.
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14 July 2018 v1.3 Submitted for approval. Approved, 17 Jul 18

GUI Re-arranged with a Stack View
Localization for France, Spain, Germany, Japan, China (Simplified), Korea, Thailand

22 Oct 2017 v1.2 Approved and available

Added t-test for significance of mean from zero or some other specified value. One-sample t-test. This can also be used for paired t-test where the mean and standard deviations entered for the difference between the paired values.

17 Sep 2017 v1.1 Approved and available

Updated for iOS11 and iPhone X

11 May 2016 v1.0.2 Approved and available

Interface update

5 May 2016 v1.0.1 Approved and available

Updated user interface with better scaling for each iPhone screen size.

10 Feb 2016 v1.0.0 Approved

Unpaired t-test: Unequal or Equal variance and Unequal sample size

Example Data

	30.02	29.89
	29.99	29.93
	30.11	29.72
	29.97	29.98
	30.01	30.02
	29.99	29.98
	30.00
	30.04
Mean	30.01625	29.92
Std Dev	0.04340425	0.1078888
n	8	6

The result using R Studio and R

Using the Welch-Satterthwaite Method

> b1
 [1] 30.02 29.99 30.11 29.97 30.01 29.99 30.00 30.04
 > b2
 [1] 29.89 29.93 29.72 29.98 30.02 29.98
> sd(b1)
 [1] 0.04340425
 > sd(b2)
 [1] 0.1078888
> t.test(b1,b2)
 
 Welch Two Sample t-test
 
 data:  b1 and b2
 t = 2.0636, df = 6.2221, p-value = 0.08296
 alternative hypothesis: true difference in means is not equal to 0
 95 percent confidence interval:
 -0.01689914  0.20939914
 sample estimates:
 mean of x mean of y
 30.01625  29.92000

Using a Pooled mathod

 > t.test(b1,b2,var.equal = TRUE)
 
 Two Sample t-test
 
 data:  b1 and b2
 t = 2.3107, df = 12, p-value = 0.03943
 alternative hypothesis: true difference in means is not equal to 0
 95 percent confidence interval:
 0.005492236 0.187007764
 sample estimates:
 mean of x mean of y
 30.01625  29.92000

One Sample t-test or Paired t-test

tValue can also be used to calculate a t value when only set of data is being compared with zero or another specified value. This method can also be used for a paired t-test once the difference between paired values is calculated.

Example Data

	0.213
	0.134
	0.043
	1.34
Mean	0.4325
Std Dev	0.6090
n	4

Leave the second set of values empty.

The result using R Studio and R

> a2 <- c(0.213,0.134,0.043,1.34)
> sd(a2)
 [1] 0.6089743
> t.test(a2)
 
 One Sample t-test
 
 data:  a2
 t = 1.4204, df = 3, p-value = 0.2506
 alternative hypothesis: true mean is not equal to 0
 95 percent confidence interval:
 -0.536514  1.401514
 sample estimates:
 mean of x
 0.4325

And data for a paired t-test

> b1
 [1] 30.02 29.99 30.11 29.97 30.01 29.99 30.00 30.04
> b2
 [1] 29.89 29.93 29.72 29.98 30.02 29.98 29.97 30.01
> c1 <- b1-b2
> c1
 [1]  0.13  0.06  0.39 -0.01 -0.01  0.01  0.03  0.03
> sd(c1)
 [1] 0.1336774
> t.test(b1,b2,var.equal = TRUE,paired = TRUE)
 
 Paired t-test
 
 data:  b1 and b2
 t = 1.6662, df = 7, p-value = 0.1396
 alternative hypothesis: true difference in means is not equal to 0
 95 percent confidence interval:
 -0.03300709  0.19050709
 sample estimates:
 mean of the differences
 0.07875

One sample t-test tValue Screenshot

Paired t-test tValue Screenshot

References

Localization

Please let me know if I've made a mistake with these translation or if additional translations can be added, e.g. for Std Dev or n, P or df. Thanks, David Bourne (david@boomer.org)

French

German

Spanish

Japanese

Korean

Chinese (Simplified)

Thai

David Bourne (david@boomer.org)