topic Re: How to estimate the standard deviation of the difference between two means? in New SAS User https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889032#M39495 <P>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: <A href="https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.4/statug/statug_ttest_gettingstarted02.htm" target="_blank">https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.4/statug/statug_ttest_gettingstarted02.htm</A></P> <P>&nbsp;</P> <P>If you don't have the raw data, the formula for pooled standard deviation is given in many textbooks, web sites and even at <A href="https://en.wikipedia.org/wiki/Student%27s_t-test#Equal_sample_sizes_and_variance" target="_self">Wikipedia</A>, and I urge you to do a search to find the proper formula.</P> Sat, 12 Aug 2023 10:06:11 GMT PaigeMiller 2023-08-12T10:06:11Z How to estimate the standard deviation of the difference between two means? https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889023#M39493 <P>Hello!</P><P>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!</P><TABLE><TBODY><TR><TD>ages</TD><TD>sex</TD><TD>n</TD><TD>mean A</TD><TD>SD A</TD><TD>mean B</TD><TD>SD B</TD><TD>Mean diff</TD></TR><TR><TD>19-30</TD><TD>males</TD><TD>882</TD><TD>7.45825</TD><TD>2.619444</TD><TD>6.2115</TD><TD>2.150556</TD><TD>-1.24675</TD></TR><TR><TD>19-30</TD><TD>females</TD><TD>897</TD><TD>5.58875</TD><TD>2.156296</TD><TD>4.666</TD><TD>1.774074</TD><TD>-0.92275</TD></TR><TR><TD>31-50</TD><TD>males</TD><TD>2077</TD><TD>7.591</TD><TD>2.546296</TD><TD>6.32325</TD><TD>2.089815</TD><TD>-1.26775</TD></TR><TR><TD>31-50</TD><TD>females</TD><TD>2288</TD><TD>5.83275</TD><TD>2.173704</TD><TD>4.86975</TD><TD>1.78963</TD><TD>-0.963</TD></TR></TBODY></TABLE> Sat, 12 Aug 2023 04:28:44 GMT https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889023#M39493 nadiaf 2023-08-12T04:28:44Z Re: How to estimate the standard deviation of the difference between two means? https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889026#M39494 <A href="https://support.sas.com/kb/61/830.html" target="_blank">https://support.sas.com/kb/61/830.html</A> Sat, 12 Aug 2023 09:13:46 GMT https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889026#M39494 Ksharp 2023-08-12T09:13:46Z Re: How to estimate the standard deviation of the difference between two means? https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889032#M39495 <P>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: <A href="https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.4/statug/statug_ttest_gettingstarted02.htm" target="_blank">https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.4/statug/statug_ttest_gettingstarted02.htm</A></P> <P>&nbsp;</P> <P>If you don't have the raw data, the formula for pooled standard deviation is given in many textbooks, web sites and even at <A href="https://en.wikipedia.org/wiki/Student%27s_t-test#Equal_sample_sizes_and_variance" target="_self">Wikipedia</A>, and I urge you to do a search to find the proper formula.</P> Sat, 12 Aug 2023 10:06:11 GMT https://communities.sas.com/t5/New-SAS-User/How-to-estimate-the-standard-deviation-of-the-difference-between/m-p/889032#M39495 PaigeMiller 2023-08-12T10:06:11Z