Appropriate Conclusions

Your conclusions summarize how your results support or contradict your original hypothesis. Discussion of the research project includes suggestions for improvements, refinement, and/or new approaches to experimental design and includes a discussion of future research questions. Conclusions are based on the analysis and are clearly related to the problem and previous studies.

This exercise will take a look at one important aspect of your conclusions: Are the conclusions valid and/or viable based upon the evidence you have provided?

Example: Using the figure (attached below), Ice Duration on Lake Mendota, 1855-2000, decide which of the three conclusions below is appropriate.

Background: One challenge to our understanding of environmental effects due to global warming is lack of data collected over long periods of time. The data from lakes in Wisconsin spans 150 years. The data are the duration of ice cover for Wisconsin's Lake Mendota, which is part of the North Temperate Lakes Long-Term Ecological Research site. Each of these measures may provide different types of evidence related to global change.

First, take a look at these questions:

    • What is the longest period of ice duration in each 20-year data set?
    • What is the shortest period of ice duration in each 20-year data set?
    • How does this compare to the average ice duration over 150 years?
    • What are the longest and shortest periods of ice duration in the entire data set? In what years do they occur? Based upon your knowledge, what other trends have comparable curves?

Now, which conclusion best describes or explains the implications of the data?

A. These data on ice cover provide evidence for global climate change.

B. These data on ice cover provide conclusive evidence for global climate change.

C. These data on ice cover do not provide evidence for global climate change.

Lastly: What other kinds of data do you think you need to make your arguments stronger?


Adapted from; Changes in Lake Ice: Ecosystem Response to Global Change Robert E. Bohanan, Marianne Krasny, and Adam Welman, TIEE Vol 3, 2005.