Interpreting Graphs PDF

Interpreting Graphs ✔ Why bother with graphs? ✔Line Graphs ✔Constructing Line Graphs ✔Bar Graphs ✔Pie charts ✔Scatter plots  How to Interpret Graphs What patterns or trends can you identify?  Why are graphs useful? Graphs are a quick way to visualize trends or to make comparisons. W...

Interpreting Graphs ✔ Why bother with graphs? ✔Line Graphs ✔Constructing Line Graphs ✔Bar Graphs ✔Pie charts ✔Scatter plots  How to Interpret Graphs What patterns or trends can you identify?  Why are graphs useful? Graphs are a quick way to visualize trends or to make comparisons. What patterns or trends can you identify? Graphs provide a visual, as opposed to text. What do you immediately notice? Looks like all those hours of science class paid off This is a simple line graph charting temperature. Temperature is labeled on the "y" axis and the dates (Jan 1-7) is labeled on the "x" axis. During the first week of January, which day was the January 1st coldest? ______ What was the temperature on o ~39 January7th? ______ F Which day does the temperature peak? January ____ 4th What is the IV? DV? The respondent variable is the temperature, the independent variable are the dates.  What if time isn’t a variable on your graph? Usually the X axis has the independent variable (what you can manipulate or adjust) and the Y has the responding variable (what is measured/counted/observed) Multiple carts are pushed down a track with different sized weights attached to them. The distance traveled was measured. Distance (m) 100 90 80 Weight Distance 70 60 1 kg 150 m 50 40 2 kg 140 m 30 3 kg 120 m 20 4 kg 90 m 10 5 kg 70 m 1 2 3 4 5 6 7 6 kg 50 m 7 kg 30 m Weight (kg) Line graphs can have multiple lines What patterns or trends can you identify? Practice making statements. Practice: What if the data is not so easy to place? What type of graph and why? Temperature & Number IV? DV? Range for each? of turtle eggs hatched (out of 20) 16 *C = 3 eggs 18 *C = 4 eggs 20 *C = 7 eggs 22 *C = 11 eggs 24 *C = 16 eggs 26 *C = 17 eggs IV is Temperature *C, range = 16 to 26 DV is Number of Hatchlings, range = 3 to 17 Graphs show us trends and relationships among data. There are generally two types of relationships that data will exhibit: inverse and direct. If one variable increases and the other decreases- they share an inverse relationship. If both variables increase or decrease together- they share a direct relationship. Inverse Relationships- As one variable increases, the other factor decreases. Examples) As you exercise more, your risk for heart disease decreases. The farther I drive, the less distance I have to reach my destination. Direct relationships occur when the two variables increase or decrease together. Examples: The higher your temperature, the higher your perspiration rate is. As the diameter of a pipe increases, the flow of water through the pipe also increases. Line of Best Fit Line of Best Fit Bar Graphs are used to compare values. What is the most common shoe length? ___________ 27 cm What is the least common shoe length? ___________ 21, 29, 30, 31 cm How many people have shoes that are 26 cm long? ________ 2 Pie charts are also used to compare parts to the whole (usually as a percentage but not always). What can you expect to spend most of your time doing at Disneyland? What can you expect to spend least of your time doing at Disneyland? Roughly what percent of Federal spending does national defense account for? ~20% Roughly what percent does our nation spend on education? ~4% Scatterplots are used to compare trends among many data points.  What type of relationship is shown by the data? Positive Direct age What do each of the dots represent? _______________ ~43 Approximately how old are husbands of 40 yo wives?____________ ~65 Approximately how old are wives of 70 yo husbands?____________ ~38-44 MOST ages lie within which range? ________________ For each scenario, choose which type of graph would be best to use (line, bar, pie, or scatter plot). 1. To show how eating vegetables over a 10 year period can lower cholesterol. 2. To compare the leg lengths and antennae lengths of crickets. 3. To analyze the relationship between hours studying for a test and test scores among students. 4. To show the percentages of students in class that are male vs. female. 5. To compare the salaries of 4 different professions: teacher, veterinarian, software engineer, banker. For each scenario, choose which type of graph would be best to use (line, bar, pie, or scatter plot). 1. To show how eating vegetables over a 10 year period can lower cholesterol. Line graph 2. To compare the leg lengths and antennae lengths of crickets. bar graph 3. To analyze the relationship between hours studying for a test and test scores among students. Scatter plot 4. To show the percentages of students in class that are male vs. female. Pie chart 5. To compare the salaries of 4 different professions: teacher, veterinarian, software engineer, banker. bar graph  Interpreting Graphs Study the line graph and answer the following questions. 1. What information is being shown in this graph? This graph shows the effect of different concentrations of fertilizer on the growth of three different types of plants.  2. Describe the results shown for corn plants. For corn plants, the higher the concentration of fertilizer, the taller the plants will grow.  3. Describe the results shown for oak seedlings. As the concentration of fertilizer is increased, growth of oak seedlings is improved, up to a certain point.  4. Describe the results shown for rose bushes. For rose bushes, increasing the concentration of fertilizer inhibits plant growth.  5. At what fertilizer concentration do oak seedlings stop improving? At concentrations above 150 mg/L, oak seedling growth is inhibited.  6. What was the height of the tallest plant used in this experiment? Corn grew to an average height of around 33 cm when the fertilizer concentration was 250 mg/L. 7. For which plant is this fertilizer least effective at Rose buses. higher concentrations?  8. Which plant shows the best growth when the fertilizer concentration is 100 mg/L? Oak seedlings 9. Predict how tall corn plants might be when the The plants will be fertilizer concentration is approximately 12 - 75 mg/L. 13 cm in height.  10. Consider the three types of plants used in this experiment. What reasons might explain why the results turned out as they did? There is no correct answer. Let’s brainstorm! Possible answers: Plants that produce a large fruit (corn) need more fertilizer. Plants that produce a large woody stem (oak trees) grow best with moderate concentrations of fertilizer. Monocots (corn) require more fertilizer than dicots. Roses are routinely fertilized. Perhaps the addition of this fertilizer made the soil toxic to the rose bush.  Study the bar graph to the right and answer the following questions: 1. Do fish grow to a larger weight in pond water or in tap water? Pond water. 2. Which grow larger, the males or the females? Females 3. What is the average weight of female fish when grown in pond water? Approximately 6.4 g. 4. What is the average weight of male fish when grown in tap water? Approximately 5.5 grams. 5. Why do you suppose the fish grow the best in pond water? Some possible answers might include: The tap water contains chlorine and fluorine, which might affect the growth of fish. Tap water does not contain all the various minerals and ions that might be found in pond water.  Making a Data Effect of Temperature on Different Enzymes Rate of Table Reaction Reaction Rate of Enzyme (seconds) As scientists collect data, it must be recorded in an organized Type of Enzymes fashion. Temp T1 T2 T3 *C Any time data is collected in an experiment, it is most often presented in a table. The data table must have a title, rows, columns, and heads. The title should be placed at the top to tell the observer what information is contained in the At the top of each column table. should be a header that tells you what information is in the column.  EXAMPLE: Make a data table for the following information. The number of cricket chirps was recorded on two different nights at various temperatures (Celsius). On night 1, the following data was obtained: Temp 16, cricket chirps 33; Temp 18, cricket chirps 38; Temp 20, cricket chirps 42; Temp 22, cricket chirps 46; Temp 24, cricket chirps 50. On night 2, the following data was obtained: Temp 16, cricket chirps 32; Temp 18, cricket chirps 36; Temp 20, cricket chirps 41; Temp 22, cricket chirps 43; Temp 24, cricket chirps 51. In the top row, place the The number of cricket chirps recorded at different temperatures title of your data table. Night 1 Night 2 In the next row, place Temp # Chirps Temp # Chirps the two column heads. Since data was 16 33 16 32 obtained on two different nights, you 18 38 18 36 will need 4 columns. 20 42 20 41 In the remaining rows, 22 46 22 43 fill in the data. 24 50 24 51  Analysis Questions Under what circumstance would each of the following types of graphs be best used? a) Line Graph: Line graphs are often used to show change over time and can be used to compare two or more sets of data. b) Bar Graph: Bar graphs are useful for showing comparisons of data collected by counting. c) Circle Graphs: Circle graphs are best used to give the viewer an overall or broad picture view of smaller groups of data and how the smaller groups fit into the whole.  Analysis Questions 2. How is a graph similar to a data table? Both are methods of organizing information. 3. Does a steep curve on a line graph indicate a rapid or slow rate of change? Rapid.  Analysis Questions 4. You are conducting a photosynthesis experiment to determine how much oxygen is produced over a 24 hour period of time. You are measuring the oxygen production every hour for 24 hours. a) What type of graph is best used to represent this data? Line graph b) When you construct a graph of your data, which variable will be placed along the x-axis? Time c) When you construct a graph of your data, which variable will be placed along the y-axis? Oxygen production  Analysis Questions 5. What is an advantage of using multiple lines on the same graph? It allows you to show comparisons between different groups of data.  Pie Graph Parts in Comparison to the whole  Line Graph Change over time  Bar Graph Comparing Data Scatter Plot Graph relationship between 2 different things