beamer：三个图并排，与 itemize协调

Question

在beamer使用叠加的幻灯片中，我希望两个在itemize环境中顺序显示三个项目，并分别在左侧、中间和右侧出现相应的图形。

在下面的 MWE 中，我使用三个minipages 分隔\hfill图形，这导致中间的图形跳来跳去。我怎样才能让第二个<2->图形保持与幻灯片相同的位置<3->？

\documentclass[10pt,table]{beamer} 
\usepackage{mwe} % <-- for dummy images

\begin{document}

\begin{frame}
  \frametitle{Plots: Data, Model, Data + Model}
  Example: Linear model--- Prestige $\sim$ Income + Education + Type
  \begin{itemize*}
    \item <1->Data plot:  \alert{marginal} relation of Income on Prestige
    \item <2->Model (effect) plot: \alert{conditional} fitted values, controlling for other variables 
    \item <3->Data + Model plot: Effect of Income (model) + \alert{partial residuals} (data)
  \end{itemize*}

    \vspace{1ex}

  % three figs side-by-side
    \begin{minipage}[c]{.33\textwidth}
     \includegraphics<1->[width=1\linewidth,clip]{example-image-a}
     \end{minipage}%
    \hfill
    \begin{minipage}[c]{.33\textwidth}
     \includegraphics<2->[width=1\linewidth,clip]{example-image-b}
     \end{minipage}%
    \hfill
    \begin{minipage}[c]{.33\textwidth}
     \includegraphics<3->[width=1\linewidth,clip]{example-image-c}
    \end{minipage}

\end{frame}
\end{document}

Answer 1

\phantom在第一张和第二张幻灯片上使用经过授权的第三张图片：

\documentclass[10pt,table]{beamer} 
\usepackage{mwe} % <-- for dummy images

\begin{document}

\begin{frame}
  \frametitle{Plots: Data, Model, Data + Model}
  Example: Linear model--- Prestige $\sim$ Income + Education + Type
  \begin{itemize}
    \item <1->Data plot:  \alert{marginal} relation of Income on Prestige
    \item <2->Model (effect) plot: \alert{conditional} fitted values, controlling for other variables 
    \item <3->Data + Model plot: Effect of Income (model) + \alert{partial residuals} (data)
  \end{itemize}

    \vspace{1ex}

  % three figs side-by-side
    \begin{minipage}[c]{.33\textwidth}
     \includegraphics<1->[width=1\linewidth,clip]{example-image-a}
     \end{minipage}%
    \hfill
    \begin{minipage}[c]{.33\textwidth}
     \includegraphics<2->[width=1\linewidth,clip]{example-image-b}
     \end{minipage}%
    \hfill
    \alt<3>{%
    \begin{minipage}[c]{.33\textwidth}
     \includegraphics<3->[width=1\linewidth,clip]{example-image-c}
    \end{minipage}}{%
    \begin{minipage}[c]{.33\textwidth}
     \phantom{\includegraphics[width=1\linewidth,clip]{example-image-c}}
    \end{minipage}}
\end{frame}

\end{document}

结果动画：