Aim #62: How Do We Create a Scatter Plot? (Unit 6 - Statistics)

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Aim #62: How do we create a scatter plot? (Unit 6 - Statistics) Homework: HW #62 Handout Scatter Plots Do Now: 1) Consider the graph below. a) Do you see a pattern in the scatter plot, or does it look like the data points are scattered? b) How would you describe the relationship between elevation and mean number of clear days for these 14 cities? That is, does the mean number of clear days tend to increase as elevation increases, or does the mean number of clear days tend to decrease as elevation increases? c) Do you think that a straight line would be a good way to describe the relationship between the mean number of clear days and elevation? Why do you think this? 2) The scatter plot below shows number of cell phone calls and age. Is there a relationship between number of cell phone calls and age? If there is a relationship between number of cell phone calls and age, does the relationship appear to be linear? Scatter Plots A scatter plot is an informative way to display numerical data with two variables. (bivariate set of data) A scatter plot may show whether the relationship between the two sets of measurements is approximately linear. Types of Associations 1) positive association: 2) negative association: as x increases, y increases as x increases, y decreases 3) no association: 4) nonlinear association: no relationship Which of the graphs above appear to model a linear relationship? 1) The scatter plot below compares frying time and moisture content. a) Is there a relationship between moisture content and frying time, or do the data points look scattered? If so, what type of association is shown? If nonlinear, state the type of association that exists. b) Describe the relationship that exists between frying time and moisture content. 2) Farmers sometimes use fertilizers to increase crop yield, but often wonder just how much fertilizer they should use. The data shown in the scatter plot below are from a study of the effect of fertilizer on the yield of corn. a) What type of association does the scatter plot show? If nonlinear, state the type of association that exists. b) Describe the relationship that exists between fertilizer and crop yield. Unit 6 Quiz on Friday! (Aims #62-65) Attachments ANGLE OF ELEVATION AND ANGLE OF DEPRESSION.gsp.

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