Page 154 of Schweser has a problem where the t-stat needs to be derived at 34 dof. How do they get 2.03 precisely? At 30 dof, the t-stat is 2.042 and at 40 dof the t-stat is 2.021. Is there an interpolation formula or is it a random approximation?

It’s just an approximation. It actually doesn’t make a difference (see the example on the page 157, t=2.04 for df=34) Cheers,

2.042 + (34-30)/(40-30)*(2.021-2.042) = 2.0336 Simple Linear Interpolation…

or use TDIST function in Excel to get the exact value but in most cases it will not make a difference. You’re very unlikely to get a question where that small a difference changes the outcome. In most cases you can estimate the t-value by eye-balling the standard error and estimate (or whatever variables you’re given - I don’t have the question in front of me) - only look it up when it looks like it might be line-ball

Thanx all… @cpk-Perfect.