Equations didn't fit

I created a presentation with University of Hamburg beamer theme, which can be found here. However, in a slide, I wrote long equations but they did not fit and I cannot fix this problem. This is the print screen of this slide. • Use the split environment of the amsmath package to split the equations and use two lines for each. – sebschub Sep 21 '12 at 8:50
• That's not possible. It does not look good and also, I have to put all these three equations in one slide. – ARAT Sep 21 '12 at 8:55
• Or since splitting the equations will make multiple lines so you will go off the bottom of the screen you could use \small but perhaps there is too much information on one slide and you should split but then use two slides. – David Carlisle Sep 21 '12 at 8:55
• I think you are falling into the trap of putting far too much on one slide: Till's advice in the beamer manual on structuring a talk is very good, and he warns against using too many equations! – Joseph Wright Sep 21 '12 at 9:06
• Additionally, eq numbering on a presentation is an instant distractor and tells the audience a bit of your attitude. They have no way to scroll back in your presentation so eq. numbering is redundant. If necessary they will point out the slide using the slide number. (Unless you distribute them as lecture notes which is still not a good idea) – percusse Sep 21 '12 at 9:31

If you really need to do this, then there is the shrink option to the frame environment in beamer. One writes \begin{frame}[shrink=20] to get at least a 20% reduction in size. So a minimal version of your example looks like:

\documentclass{beamer}

\begin{document}

\begin{frame}[shrink=20]
\frametitle{Vector Error Correction Models}
\begin{equation}
\Delta X_t = \alpha_0 + \sum_{i=1}^I a_i \Delta X_{t-i} +
\sum_{j=1}^J b_j \Delta Y_{t-j} + \sum_{k=1}^K c_k \Delta Z_{t-k}
+ \Theta \mu_{t-1} + \epsilon_t
\end{equation}
\end{frame}

\end{document}

producing whereas without shrink one gets: Note the shrink option implies the squeeze option, which removes alot of the vertical spacing. See the beamer userguide for more information.