Bellwork Sept 14, 2015 SPI 0807.Inq.5: Cause and Effect 1. Which most likely causes the paper to spin? 2.By inserting a gene into crop plants, scientists have developed plants that are resistant to insects. If an insect eats the plant, the insect dies. Which practice is unnecessary with this new plant variety? a. spraying plants with pesticides b. overproducing food crops c. removing weeds from crops 3.A student filled three identical cups with equal amounts of water. The student placed each cup in a room with a different air temperature. After a few days, the student compared the amounts of water remaining in each cup. What cause- and-effect relationship does this investigation support?

Bellwork Sept 14, 2015 SPI 0807.Inq.5: Cause and Effect 1. Which most likely causes the paper to spin? 2.By inserting a gene into crop plants, scientists have developed plants that are resistant to insects. If an insect eats the plant, the insect dies. Which practice is unnecessary with this new plant variety? a. spraying plants with pesticides b. overproducing food crops c. removing weeds from crops 3.A student filled three identical cups with equal amounts of water. The student placed each cup in a room with a different air temperature. After a few days, the student compared the amounts of water remaining in each cup. What cause- and-effect relationship does this investigation support? Heat rising A Higher the temperature, the more the water evaporates

Today's Plan Plan 1) Do and review Bellwork 2) Go Over Objectives 3) Quick Review over cause and effect 4)Quiz over cause and effect 5) Notes on Bias and error WRITE THIS IN YOUR AGENDA! Homework: NONE Sept 14, 2015 SPI 0807.Inq.5: Bias and Error

Notes 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. Bias Is Bad! Bias  Science is about obtaining accurate results so bias should NEVER be allowed to influence your experimental results! Bias Science SPI 0807.Inq.5: Bias and Error 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.

Notes 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. Science SPI 0807.Inq.5: Bias and Error This is BIAS, and it should NEVER be allowed in science.

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. Notes Science SPI 0807.Inq.5: Bias and Error BIAS should NEVER be allowed in science experiments!

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 Notes Bias in Science Answer: These two students are biased towards Justin Beiber, so their results will probably be biased and wrong too Science SPI 0807.Inq.5: Bias and Error BIAS should NEVER be allowed in science experiments!

 Humans are imperfect, so bias happens both intentionally and unintentionally Notes Solutions to Bias in Science Science SPI 0807.Inq.5: Bias and Error 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

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

Notes SPI 0807.Inq.5: Bias and Error Famous Bias in Science Science Direct Current vs Alternating Current Bias: Edison promoted direct current electricity, but Nikola Tesla promoted alternating current for the Westinghouse Electric Company. 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

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 Notes SPI 0807.Inq.5: Bias and Error Errors in Science 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) Notes SPI 0807.Inq.5: Bias and Error Errors in Science Science

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

Notes SPI 0807.Inq.5: Bias and Error Famous Errors in Science Science Mars Climate Orbiter: Expensive Mistake: launched by NASA in December 1998, this robotic spacecraft was designed to study weather on Mars. 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

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

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

He wrongly concluded that the features on Mars were canals built by extraterrestrials (Martians) Notes SPI 0807.Inq.5: Bias and Error 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. Later observations by others confirmed that there are no signs of intelligent life on Mars. Famous Bias and Errors in Science