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10. Consider the wage equation $\ln(wagei) = \beta0 + \beta1 educi + ui$, where ui contains unobserved ability abilityi and local labor-market quality Li. Assume Cov(educi, abilityi) > 0and Li directly affects wages. A proposed instrument is distance to nearest college, zi. Suppose zi is strongly correlated with Li (e.g. urban areas have smaller distance and higher wages even holding education fixed), and $L_i$ is omitted from the regression. Which statement is most correct?(A) The exclusion restriction may fail because \( z{i} \) can affect \( \ln (wage{i}) \) through \( L{i} \), so \( Cov(z{i},u_{i}) \) may be nonzero.(B) If is always consistent regardless of \( L_i \)(C) Adding an intercept is sufficient to control for \( L_{i} \)(D) If OLS is biased, IV must be unbiased in finite samples

9. Suppose you estimate a log-level model $\ln(yi) = \beta0 + \beta1 xi + ui, \quad yi > 0,$with $E(ui \mid xi) = 0$. Using the standard approximation for small changes, which interpretation of $\beta_1$ is correct?(A) A one-unit increase in \( x \) changes \( y \) by exactly \( \beta_{1} \) units(B) A one-percent increase in \( x \) changes \( y \) by approximately \( \beta_{1} \) percent(C) A one-unit increase in \( x \) changes \( E(y \mid x) \) by approximately \( 100\beta_{1} \) percent(D) \( \beta_{1} \) is the price elasticity of demand

8. Let a categorical variable $Gi \in \{1,2,3,4\}$ and define dummies $D{ki} = \mathbf{1}\{Gi = k\}$, $k = 1,2,3,4$. Consider the regression with an intercept: $yi = \beta0 + \beta1 D{1i} + \beta2 D{2i} + \beta3 D{3i} + \beta4 D{4i} + ui$. Which statement is correct?(A) The model is identified because the dummies are mutually exclusive(B) The model is not identified because \( \sum{k=1}^{4} D{ki} = 1 \) for all \( i \); drop one dummy or drop the intercept(C) The model is identified if \( n \) is large enough(D) Identification fails only if one group has zero observations試題隨卷繳交接背面4國立臺北大學 115 學年度碩士班一般入學考試試題系(所)組別:經濟學系科 目:統計學第4頁 共4頁☑可 ☐不可使用計算機

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13.下列有關股四頭肌(quadriceps femoris)的敘述,何者錯誤? (A)股四頭肌收縮可伸直小腿(extend leg at knee joint) (B)股四頭肌收縮可屈曲大腿(flex thigh at hip joint) (C)股四頭肌的外側部可作為肌肉注射位置 (D)股四頭肌的內側部是股三角(femoral triangle)的內側邊界

16.班上進行閱讀積分活動,學生每讀完一本書可獲得一點。小睿讀的是厚重的科普書,花了兩週讀完一本;其他同學 讀短篇故事書,一週可累積數本。當教師公布積分排行榜時,小睿情緒激動地說:「這不公平!你們只看數量,不看 難度和理解深度。」教師發現他並不是不喜歡閱讀,而是非常在意評分制度是否合理。依據資優學生情意特質,下 列哪一項處理最適切? (A)先接納小睿對公平性的敏感,再引導全班討論閱讀評量是否可納入難度、理解深度或心得品質等指標。 (B)告訴小睿所有學生都使用同一套規則,這就是公平,避免個別學生因能力較強而要求特殊標準。 (C)讓小睿改讀較短的書,使他能在現有制度中取得較高積分,減少因排名造成的挫折。 (D)取消排行榜,避免資優學生因過度在意公平而產生情緒反應。

4. 當P型及N型材料相接觸時,即會產生一空乏區,而P型半導體之空乏區內應有 (A) 電洞 (B) 電子 (C) 負離子 (D) 正離子。

5. 下列有關共集極放大電路之敘述何者正確? (A) 信號由集極輸入 (B) 輸入電阻高 (C) 射極電壓的平均值永遠為0V (D) 又稱集極隨耦器。