Hello!
I've trying to estimate the SD of the difference between two means. I have the means, SD and n for each dataset. Below an example of how I have my dataset. I'd appreciate any help with this. Thanks!
ages | sex | n | mean A | SD A | mean B | SD B | Mean diff |
19-30 | males | 882 | 7.45825 | 2.619444 | 6.2115 | 2.150556 | -1.24675 |
19-30 | females | 897 | 5.58875 | 2.156296 | 4.666 | 1.774074 | -0.92275 |
31-50 | males | 2077 | 7.591 | 2.546296 | 6.32325 | 2.089815 | -1.26775 |
31-50 | females | 2288 | 5.83275 | 2.173704 | 4.86975 | 1.78963 | -0.963 |
Your table seems to be just the summary statistics. If you have the raw data, then PROC TTEST does this easily, see figure 125.4 here: https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.4/statug/statug_ttest_gettingstarted02.htm
If you don't have the raw data, the formula for pooled standard deviation is given in many textbooks, web sites and even at Wikipedia, and I urge you to do a search to find the proper formula.
Registration is open! SAS is returning to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. Register for just $495 by 12/31/2023.
If you are interested in speaking, there is still time to submit a session idea. More details are posted on the website.
For SAS newbies, this video is a great way to get started. James Harroun walks through the process using SAS Studio for SAS OnDemand for Academics, but the same steps apply to any analytics project.
Find more tutorials on the SAS Users YouTube channel.