1. Do Now
1. Get a copy of the data that you got during the lab on Thursday/Friday. Complete any and all calculations that are required by your lab.

2. Why Statistics Matters!

3. Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data
How do you know if data is good or not?
Statistics allows for us to call data good or bad!

4. Calculating an Average
An average is a measure of the overall data.
Gives the value that the data tends towards

5. Problems with an Average
Averages can hid just how bad your data is.
Averages also can make your data look worse than it actually is

6. Calculating Standard Deviation
A standard deviation tells us how much variance exists within an average.
This will tell your reader if the average accurately reflects the data or if it is lying to you.

7. Class Example
You have the following data and average. Calculate the standard deviation.
Trial
Speed (m/s) 1 20 2 30 3 4 35
Average
28.75

8. Table Talk
You have the following data and average. Calculate the standard deviation
Trial
Speed (m/s) 1 5 2 3 10 4 20
Average

9. Why is a Standard Deviation Important?
Tells us the reliability of our data
A huge standard deviation tells the reader that even if the average is close to the actual value, that the actual data is not reliable.
A small standard deviation tells the reader that you had very precise data.

10. Calculate Average and SD
Go to your data and calculate the average and standard deviation (if necessary).
If you only ran one trial, than complete any other calculations you may have not already finished.
NOTE – Everyone must have a standard deviation present when reporting averages.

11. 1 2 3 4
Compare Your Procedure to Book
Pick experiment
Research Topic
Develop Procedure 8 5 7 6
Develop 3rd Procedure to Minimize Experimental Error
Develop 2nd Procedure to Minimize Experimental Error
Calculations and Analyze Data
1st Run Through of Lab 9 10 11 12
Write Discussion and Introduction
Make Poster for Presentation!
2nd Run Through of Lab
Calculations and Analyze 2nd Data

12. Modify Your Procedure
After you complete the statistics, determine if you have good or bad data.
You will be running the lab again tomorrow with modifications based on how the first run through went.
You must submit the final modifications to the procedure by the end of class.

14. Closing Time
Turn in final results, tables, and statistics before leaving.
If you have not gotten through the modification of your procedure, then this should be done before you come to class next!