Bias and Error in Science

1. Instructions 1) First click on "View" from the top-menu bar. 2) Then click on "Slide Show" from the drop-down menu. 3) Then use the right-arrow button on your keyboard to advance through this presentation. SPI 0807.Inq.5: Bias and Error Notes Science Bias and Error in Science Bias:this means you are prejudiced towards or against something and that you allow your views to affect the results of your experiment. • Science is about obtaining accurate results so bias should NEVER be allowed to influence your experimental results! Bias Is Bad! Bias Bias

2. SPI 0807.Inq.5: Bias and Error Notes Science Bias in Science Experiments Example: Imagine that you doing an experiment to determine which NFL football quarterback can throw a football the furthest. Your favorite football team is the Tennessee Titans, so you are disappointed with your data when you notice that the Titans' quarterback's throwing distance is not the furthest. Yet because this is your favorite quarterback, you change the data so that this quarterback appears to throw the furthest. This is BIAS, and it should NEVER be allowed in science.

3. SPI 0807.Inq.5: Bias and Error Science Notes Example: Bubba loves to eat french fries with lots of extra salt. He conducts an experiment to determine how much better french fries taste with lots of extra salt. Identify the bias or error in this situation ANSWER:Because Bubba likes extra salt on his fries, he wrongly assumes that everyone else will like extra salt too. He is biased toward salt, so his results will contain errors. BIAS should NEVER be allowed in science experiments!

4. SPI 0807.Inq.5: Bias and Error Notes Science Bias in Science Two students who love Justin Bieber’s music do an experiment to measure how long people have to hear one of Justin’s songs before they too fall in love with his music. Question: Which choice below most likely will occur? (Just write the correct letter) A) Bias B) Fraud and Waste C) Song and Dance Answer:These two students are biased towards Justin Beiber, so their results will probably be biased and wrong too BIAS should NEVER be allowed in science experiments!

5. SPI 0807.Inq.5: Bias and Error Notes Science Solutions to Bias in Science • Humans are imperfect, so bias happens both intentionally and unintentionally Ways to Reduce and/or Eliminate Bias • Be aware that bias can and does happen • Strive to recognize it, and eliminate it from your experiments. • Follow the steps and principles of the scientific method • Make sure that others rigorously review your work looking for bias

6. SPI 0807.Inq.5: Bias and Error Notes Science Famous Bias in Science Thomas Edison and Direct Current Electricity Inventor: Thomas Edison

7. SPI 0807.Inq.5: Bias and Error Notes Science Famous Bias in Science Direct Current vs Alternating Current Edison promoted direct current electricity, but Nikola Tesla promoted alternating current for the Westinghouse Electric Company. Bias: Experiments had clearly demonstrated that alternating current was more efficient and less expensive. Yet Edison refused to yield to facts. Nearly all electricity generated today is alternating current

8. SPI 0807.Inq.5: Bias and Error Notes Science Errors in Science • Avoid Mistakes: • One small error can result in all your experimental data being wrong • So scientists work very hard to avoid making mistakes • Peer Review: • One key way scientists deal with this issue is by having other scientists review their work to check for mistakes • This very common practice is called peer review

9. SPI 0807.Inq.5: Bias and Error Notes Science Errors in Science • To Avoid Mistakes: • Make sure you are following the steps of the scientific method • Make sure you have only one independent variable at a time • Make sure you correctly identify your dependent variables • Make sure you include valid control experiments • Make sure you record in detail every step of your experiment • Ask someone else to review all your work (peer review)

10. SPI 0807.Inq.5: Bias and Error Notes Science Famous Errors in Science Mars Climate Orbiter:

11. SPI 0807.Inq.5: Bias and Error Notes Science Famous Errors in Science Mars Climate Orbiter: launched by NASA in December 1998, this robotic spacecraft wasdesigned to study weather on Mars. Expensive Mistake: A design team used standard units (pounds- seconds) while a different design team used metric units (newtons- seconds). So instead of orbiting Mars, the spacecraft crashed to the surface of the red planet. Cost of this mistake: $327 million dollars

12. SPI 0807.Inq.5: Bias and Error Notes Science Famous Bias and Errors in Science Canals on Mars Astronomer: Percival Lowell

13. SPI 0807.Inq.5: Bias and Error Notes Science Famous Bias and Errors in Science From 1894 to 1908 Percival studied the planet Mars with a large telescope.

14. SPI 0807.Inq.5: Bias and Error Notes Science Famous Bias and Errors in Science Percival was fascinated about the possibility of intelligent life on Mars . He was biased about this. He observed hazy images of the surface of Mars His bias lead him to make significant errors about what he saw. He wrongly concluded that the features on Mars were canals built by extraterrestrials (Martians) Later observations by others confirmed that there are no signs of intelligent life on Mars.