4 Qualitative – descriptions (Mary has red hair.) Quantitative – numbers (Mary was walking two dogs today.)When doing observations we ask:“Who” is that“What” is that“When” is that happening“Where” is that taking place
5 Observation: the fact, the cat is lying on the ground Inference – logical conclusion based on reasoningThe cat is dead.The cat is asleep.Why is the cat asleep? The cat is asleep because he is tired.Interpretation – observation plus our personal value systemThe cat is so cute!
6 You will observe the following picture for a few seconds. Look at everything you think might be important.
8 Scientific MethodScientists use their observations to come up with questions and use the answers to solve problems. Scientists develop and TEST ideas using a systematic, step by step approach called the scientific method. The exact steps vary, but always include the following ideas.
9 II. Steps of the Scientific Method Posing questions, developing hypotheses, designing an experiment, collecting and analyze data, drawing conclusions, and communicating with other scientists.In other words, it’s a way to solve a problem.
10 Step 1: Posing Questions Define the focus of the researchObserve the world around you using all senses to gather information.Read books or other scientists’ researchMake sure your question is scientificCan be answered with evidenceNOT answered with an opinion
11 Step 2: Develop a hypothesis A hypothesis is a testable, educated guess to answer your question or is a possible solution to the problem based on your research or observationsYour prediction, use “I think…”Must be TESTABLE!!
12 Step 3: Design an Experiment Parts of an experiment:Parameter: something that can be measuredThe parameter being tested is the manipulated variable or independent variable. This is what you are manipulating or changing on purposeThe parameter that you are measuring is called the responding variable or dependent variable. It changes in response to or because of the manipulated variable
13 Step 3: Design an Experiment (cont) The parameters that don’t change are called the controls or constants. Your control group is used for comparison.The controls DO NOT change so you can be more sure that your manipulated variable CAUSED your responding variable to change,A controlled experiment is an investigation where only ONE parameter is manipulated at a time.
14 Step 4: Collecting and Analyze Data Data are the facts figures and other evidence gathered through observationsAs you collect the data you got from your experiment, write it down.Organize your data into a chart, table, or graphUse pictures or photos to explain your resultsAnalyze your data by writing a summary of what happened in your experiment.
15 Step 5: Draw Conclusions Do the results of your experiment support your hypothesis or not?A conclusion states whether or not the data supports the hypothesis.Do you need to revise your hypothesis and retest?
16 Step 6: Communicate your results to others Share what you found out from your experimentScientists make presentations and write papers so others can repeat their experiments
17 Step 6: Communicate your results to others (cont.) Scientists use models, theories and laws to explain to people how the natural world works.Model: a picture, diagram or other representation when the real thing is not easy to seeTheory: a conclusion backed up by many scientists with the same resultsLaw: a theory that has been proven over and over again. A “rule” of nature.