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I'm using Google sheets to find TTEST scores. Its outcome is a single value, namely, p value. But in addition to this p value I also need to report degree of freedom and a t statistic value: t(degress of freedom) = the t statistic, p = p value.

Example T Test report on apa stlye: "The 25 participants who received the drug intervention (M = 480, SD = 34.5) compared to the 28 participants in the control group (M = 425, SD = 31) demonstrated significantly better peak flow scores, t(51) = 2.1, p = .04." From https://www.socscistatistics.com/tutorials/ttest/default.aspx#:~:text=The%20basic%20format%20for%20reporting,of%20t%2Dtest%20was%20used.

Where or how can I find these two values (t statistic and degree of freedom)? I appreciate your help.

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Without further context it would be hard to answer, because there are several variants of $t$-test (one sample, for independent samples with equal, or unequal variance, for dependent samples, etc.). Nonetheless, $t$ statistic and degrees of freedom are defined in terms of things like mean, standard deviation, and number of samples for both groups, where the formulas for calculating them can be found in statistics handbooks, and many places on web, including Wikipedia. I'd recommend you find the appropriate variant of the $t$-test that you are using (are you sure that the spreadsheet calculates the correct one for you?) in Wikipedia's article and calculate it by hand, you need nothing more then the pocket calculator for this.

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  • $\begingroup$ Thank you for your answer. I´m assuming type 3 T.TEST(range1, range2, tails, type) which is "a two-sample unequal variance (heteroscedastic)" as shown in support.google.com/docs/answer/6055837?hl=en from what I see this is what shows the wikipedia entry. Is there any way I can see the mentioned values in gsheet? $\endgroup$ – Arie Jul 3 at 20:55
  • $\begingroup$ @Arie don't know, but you can easily calculate them by hand and you'd probably learn more by doing it like this. $\endgroup$ – Tim Jul 3 at 22:00
  • $\begingroup$ thank you. I´m actually trying to compare the number of responses given to a test with an automatic method (no subjects involved) against the number of responses provided in a dataset that aggregates responses from 100 human subjects. There are 4 items in the test and I have the average number of responses for each item, and the overall average. I would like to compare the automatic vs the human subjects condition. $\endgroup$ – Arie Jul 4 at 14:33
  • $\begingroup$ I´m really confused since I don´t know if independent te test is appropriate adn what are the real sample sizes in this particular context (n=1 vs N=100) or just work with the averages? I appreciate your help $\endgroup$ – Arie Jul 4 at 14:33
  • $\begingroup$ @Arie this sounds more like one sample t-test, but you should ask the follow-up questions as separate questions. $\endgroup$ – Tim Jul 4 at 15:04

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