Lvl f msrmnt r scl f msr s clssfctn tht dscrbs th ntr f nfrmtn wthn th vls ssgnd t vrbls. Psychlgst Stnly Smth Stvns dvlpd th bst-knwn clssfctn wth fr lvls, r scls, f msrmnt: nmnl, rdnl, ntrvl, nd rt. Ths frmwrk f dstngshng lvls f msrmnt rgntd n psychlgy nd hs snc hd cmplx hstry, bng dptd nd xtndd n sm dscplns nd by sm schlrs, nd crtczd r rjctd by thrs. thr clssfctns ncld ths by Mstllr nd Tky, nd by Chrsmn.