washington federal reserve chair janet yellen go congress tuesday first time since republicans take control white house house legislature less clarity direction u.s. economic policy time three-year tenure detail president donald trump economic policies remain largely unknown announce rollback financial regulation detail clarity size scope time tax cut promise possible new tax import increase infrastructure spend could boost inflation send dollar soar uncertainties make unusually difficult feed chart course interest rate policy quite significant uncertainty actually go happen think anyone quite know feed vice chair stanley fischer say saturday even best time feed ability see shift economy limit 2012 say interest rat would start rise 2014 policymakers wait december 2015 first rate hike forecast four interest rate rise 2016 turn one yellen due give semi-annual testimony senate bank committee tuesday 10 a.m. est address house financial service committee wednesday american economy many estimate around feed consider full employment inflation tick 1.6 percent economy grow 1.6 percent last year base feed economic projections year could raise interest rat three time 25 basis-point step little change central bank feb. policy statement reflection little insight feed officials trump policies lot ways could go wrong like spin toward trade war say jon faust johns hopkins university economics professor former special adviser feed board governors trump advisers include national trade council director peter navarro criticize trade policies china germany fuel concern washington might disrupt global commerce time new president treasury secretary steve mnuchin stress washington continue participate global economic forums tuesday yellen likely face renew pressure lawmakers set rate policy publicly disclose mathematical formula head financial service committee house representatives say resubmit proposal make feed adopt policy rule yellen publicly oppose proposal say would damage feed ability respond crises could win traction central bank trump raft appointments make trump name members central bank washington-based board governors currently two empty seat seven-member body feed governor daniel tarullo say friday would resign around early april president may also appoint new chair yellen 4-year term chair come january 2018 fischer term vice chairman end june year feed limit view trump economic policies yellen head congress