https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36237#M1518 I want to convert percentiles (pr) to NCE. I found the following formula:<BR /> nce = invnorm(pr/100)*21.06 + 50, where invnorm is the inverse normal probability function<BR /> <BR /> I can't find invnorm anywhere in SAS. Any thoughts? Wed, 23 Mar 2011 12:12:58 GMT GreggB 2011-03-23T12:12:58Z https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36237#M1518 I want to convert percentiles (pr) to NCE. I found the following formula:<BR /> nce = invnorm(pr/100)*21.06 + 50, where invnorm is the inverse normal probability function<BR /> <BR /> I can't find invnorm anywhere in SAS. Any thoughts? Wed, 23 Mar 2011 12:12:58 GMT https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36237#M1518 GreggB 2011-03-23T12:12:58Z https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36238#M1519 I think you want the probit() function. For instance, probit(.025) is -1.96. Wed, 23 Mar 2011 13:34:01 GMT https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36238#M1519 lvm 2011-03-23T13:34:01Z https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36239#M1520 Yep. the PROBIT function changes it to a Z score. Then, you can apply the formula for NCEs. Wed, 23 Mar 2011 18:51:51 GMT https://communities.sas.com/t5/Statistical-Procedures/Converting-percentiles-to-normal-curve-equivalents/m-p/36239#M1520 GreggB 2011-03-23T18:51:51Z