the nature of science science skills n.
Skip this Video
Loading SlideShow in 5 Seconds..
The Nature of Science & Science Skills PowerPoint Presentation
Download Presentation
The Nature of Science & Science Skills

The Nature of Science & Science Skills

279 Views Download Presentation
Download Presentation

The Nature of Science & Science Skills

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. The Nature of Science & Science Skills Test Review

  2. Research starts with a … • Research question • What the scientists wants to know

  3. What are the two general types of research: • Experimental • Descriptive

  4. Descriptive research is… • Based mainly on observations

  5. Examples of descriptive research are… • Making models • Dissections • Observing animals in the wild

  6. For example… How do the survivors of a disaster react to the disaster? No variables; data is based on watching and talking to survivors

  7. Experimental research is… • The manipulation and control of variables

  8. Speaking of variables….

  9. What are the three types of variables? • Independent variables • Dependent variables • Controlled variables • Also called constants

  10. Independent variables are… • What is being tested • What is being changed • The difference between the groups • The ‘cause’ of a change

  11. Dependent variables are… • What is observed • What is measured • The data • The ‘effect’ caused by the independent variable

  12. Controlled variables are… • Things that could change, but don’t • Kept constant by the scientist • Allow for a fair test

  13. So an experimental question has to indicate the variables • How the independent variable will AFFECT the dependent variable • What the EFFECT of the independent variable will be on the dependent variable

  14. For example… • How does the temperature of ocean water affect the speed of a hurricane? • Independent variable • T of ocean water • Dependent variable • Speed of a hurricane

  15. Predictions • Educated guesses about what will happen during an investigation • Based on prior knowledge (observations, background research, etc)

  16. For example… People in disasters will react by trying to help others as much as possible. This is a PREDICTION because it’s a guess about what you think will happen.

  17. Hypothesis(plural – hypotheses) • Special kind of prediction • What makes it so special??? • It’s a guess about the VARIABLES & their relationship, in particular, • How will the independent variable affect the dependent variable?????????

  18. How to write a hypothesis • Use an If, Then statement • IF the independent variable changes, THEN the dependent variable changes • This type of sentence shows what the IV will do to the DV

  19. For example… • IF the T of ocean water increases, THEN the speed of a hurricane will increase. • This shows the expected relationship between the independent variable (the T of ocean water) and the dependent variable (the speed of a hurricane) • If the T of ocean water changes, it will cause the speed of a hurricane to change too.

  20. The null hypothesis • A statistical procedure • Stated as if there will be no relationship between the variables

  21. For example… • There is no relationship between water temperature and the speed of a hurricane

  22. Planning the investigation – Experimental Design • You absolutely, positively have to know what the variables are! • What you are changing • How you are changing • What you are measuring • How you are measuring • Repeated trials • Data tables

  23. Data tables? • Numerical (quantitative) data organized in rows and columns • The specific independent variables are listed • The number of trials are listed • Blanks are left for the data (dependent variable) to be filled in

  24. Title Describing the Data

  25. Analyzing the data • Reduce the data • Do something to make the amount of data smaller • Central tendencies • Mean (average) • Median • Mode • Range • frequency

  26. Analyzing the data • Graph the data • Lets us see trends, patterns, relationships, comparisons • Bar graphs • Let us compare data • Line graphs • Let us see trends or changes • Scatter plots • Shows correlations or associations between variables

  27. Bar graph This shows a comparison of the types and amounts of trash found on a beach

  28. Line graph This shows a change in grade point averages; the trend is an increase in GPA

  29. Scatter plotPositive Correlation An increase in the variable on the X-axis is associated with an increase in the variable on the Y-axis

  30. Scatter plotNegative Correlation An increase in the variable on the X-axis is associated with an decrease in the variable on the Y-axis

  31. Scatter plotNo Correlation Random data points – there is no association between the variables

  32. Conclusions • How we sum up the investigation • Does the data support the hypothesis? • If it does – we accept the hypothesis • If it does not – we reject the hypothesis • All back up what you say with data • Evidence • Discuss issues or problems with the investigation • Discuss the importance or relevance of the investigation

  33. Communicate what you know • Finding out something new doesn’t do anyone any good unless the new knowledge is shared • Journals & magazines • Presentations