1. Describing and Explaining Data Scientific Ways of Knowing #1

2. Vocabulary  Description  Explanation  Inference  Observation  Prediction

3. Describing and Explaining Data  Scientific practice follows the basic pattern of describing observations and trying to explain them.  It is not just scientists, though, who make descriptions and explanations.  People do such things all of the time.

4. What do you Think?  David sees smoke rising from behind Susan’s house across the street.  He calls his friend and exclaims, “Hey! There’s smoke coming up from behind your house!”  Susan responds, “Relax. We’re grilling some steaks in the backyard.”  Who made the description? _____________  Who gave the explanation? _____________

5. What do you Think?  What is the difference between a description and an explanation?  _________________________________ _________________________________ _________________________________ _________________________________ _________________________________ _________________________________

6. What do you Think?  When scientists explain their observations, they sometimes make inferences. An inference is a conclusion that compares our observations with what we think to be true.  After David saw the smoke, what inference did he probably make? __________________________________

7. What People Think  In science, a description is an accurate account of an event or process.  An explanation tells why or how that event or process happened.  An explanation might also say why that event or process is important.  A good explanation can be used to make predictions as well.

8. Practice  Which of the following is an example of an inference? a.Rutherford used his observations and what he knew about positive charges to suggest a new model for the atom. b.Rutherford did not want to disprove his former teacher’s model of the atom. c.Rutherford disproved his teacher’s model of the atom. d.Rutherford got totally unexpected results from his experiments with alpha particles.

9. Practice  How is an inference different from a prediction? a.An inference is usually not influenced by personal bias, and a prediction almost always is. b.An inference is a guess based on feelings, and a prediction is a conclusion based on facts. c.An inference is rarely used for further scientific thinking, but a prediction can lead to new discoveries. d.An inference says what is happening now, and a prediction says what will happen in the future.