Problem 3. Consider the simple regression model: Y; = Bo + B1X; + U; where X; is an endogenous regressor and Z; is a valid instrumental variable for X;. Let B1 be the OLS estimator and B2 be the IV estimator. Consider the R and R of the two estimations, which one is larger (i.e., which estimator fits in-sample Y; better)? Recall that R² is defined as: Σ E,(Y; – Ý)² EL(Y: – Ý;)? E(Yi – Ý)² E(Yi – X;ß)² E, (Y; – Ý )² - R? = 1 – = 1 %3D | i=1

Find the frequency of a musical note which is 7 half-steps above a note with frequency 260 cps. Round to the nearest whole number. (Use the formula Q-Qo*1.05946" from your notes) The frequency of the note is cps.

Solve for x

Find the distance traversed by the tip of the minute hand on a clock between 4:18 P.M. and 6:58 P.M. on any given day if the length of the minute hand is 7 inches. Answer exactly or round to 3 decimal places. The minute hand travelled inches. Preview TIP Enter your answer as a number (like 5, -3, 2.2172) or as a calculation (like 5/3, 2^3, 5+4) Enter DNE for Does Not Exist, oo for Infinity