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PEAMCQModerate

2025 PEA Q14

Two samples; R2R^2 of first >> R2R^2 of second. Which follows?

Reveal answer and solution

Answer

D

Solution

  1. 1

    For a simple regression,

  2. 2
    R2=β^12SxxSyy. R^2 = \hat\beta_1^2 \cdot \frac{S_{xx}}{S_{yy}}.
  3. 3

    A larger R2R^2 can result from a larger β^1|\hat\beta_1|, a larger SxxS_{xx}, or a smaller SyyS_{yy}. None of (A), (B), or (C) follows without further restrictions.

Answer structure / marking notes

A high R2R^2 does not imply a large slope; the variance of XX also matters.

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Content note

Imported from public/resources/isi/msqe/solutions/pea/2025/ISI_MSQE_PEA_2025_Solutions.tex. Question wording is retained from the available local TeX source; incomplete option blocks or ambiguous source status are flagged for review.