A Nutritionist Collected Information About Different .

Name: Period:Date:Notes Practice Linear ModelsA nutritionist collected information about different brands of beef hotdogs. She made a table showing the number Calories and the amount ofsodium in each hot dog.Calories perBeef HotDog186181176149184190158139Milligrams ofSodium per BeefHot Dog495477425322482587370322DIRECTIONS:1st Step: In Class Complete ALL of the TI-84 work while you are in class (in case you do nothave access to your TI-84 tonight). Write down any data that you are requested to copy from the viewingscreen on the worksheet in the space provided.2nd Step: Prep Task (if not finished) Use this information to answer the questions that follow for your Prep.TI-84 Component of Assignment- Creating A Scatter PlotTURN ON Diagnostics.1) Place the data in your L1 and L2 of your Ti-84.2) Set your Stat Plot function in the calculator to graph as a Scatter Plot.3) Zoom Stat to display the scatter plot.

1)2)3)4)5)6)7)TI-84 Component of Assignment- Creating A Linear RegressionKeep your data in L1 and L2.Create the LinReg in the STAT button. Before you command the calculator toCALCULATE, store the function in Y1 in STORE REGEQ. (ALPHA, TRACE,Choose Y1, ENTER).Now Hit enter at Calculate.Write the full decimals for “a”, “b”, and “r” in the space provided below.Create the approximate Linear Regression Equation. Round your Slope andY-intercept to the nearest hundredth.Round the Correlation Coefficient to the nearest hundredth and write it in thespace provided.Hit the GRAPH key. You should now see the Linear Regression and theScatter Plot points on the same viewing screen.TI-84 Component of AssignmentCreating Residual Values and Residual Plot Graph1) Go back to STAT, EDIT,2) Use your Cursor to move the blinking black box onto L3.3) 2nd Stat(LIST), 7:RESID,IMPORTANT REMINDER: You MUST calculate the LIN REG for the 7:RESIDchoice to be present. Remember the TI-84 calculates the residuals bydetermining the difference between your line of best fit and the scatter plot data.The TI-84 cannot do this, if you do not command it to determine a LIN REG.4) You will be back to L3. Cursor down and all your residual values shouldappear.5) Copy down these values in the table provided. Each residual valuecorresponds to a Calorie value. Round to the nearest hundredth if necessary.6) Create a Residual Plot graph Go back into STAT PLOT.7) Pick PLOT 1.8) Set your YLIST to pull values from You RESIDUALS Or L3 (which are thesame values) .2nd STAT will pull up the RESID and L3 choices.9) ZOOM #910) You should see a residual plot.11) Create a “rough sketch” of the graph is the box provided. Label with titles(Main, x-axis, y-axis).For your PREP TASK: Use the information you have gathered using your TI-84 toanswer the questions that follow.

Name: Period:Date:DATA COLLECTION: Linear ModelsTi:84 Data Collection for Prep TaskSlope, Y-intercept, and Correlation Coefficienta b r Linear Regression (Rounded to nearest hundredth)y Correlation Coefficient (Rounded to nearest hundredth)r Residual values (Rounded to nearest hundredth)Calories perBeef Hot DogResidual Plot186181176149184190158139Residual Values

PREP Questions:1) What type of correlation is present between Calories and Sodium (Ex. StrongPositive, Strong Negative, Weak Positive, Weak Negative, No Correlation)?2) What does the description you picked mean?3) What is the possible range of values for a correlation coefficient of data?4) Why does the correlation coefficient from your data provide evidence that youchose the correct correlation description in question 1.”5) Does strong correlation ALWAYS imply there is causation? EXPLAIN youranswer.6) Do you believe there is causation in the beef hotdog example? Why”For questions 7 – 9Calculate by hand, using your LinReg that has been rounded to the nearesthundredth. Note if you have access to your calculator at home, you can view thetable after you have pulled your Lin Reg into your Y1. The more exact answer willbe in the table, since the TI-84 is using the full decimal version of your LinRegEquation. This is a way to check your hand calculations. The answer will be close,but not exact.7) Interpolation: Use your Linear Regression equation to predict what the sodiumlevels would be for beef hotdog that was 140 calories.8) Extrapolation: Use your Linear Regression equation to predict what the sodiumlevels would be for beef hotdog that was 250 calories.

9) About how much calories would you expect a hot dog containing 500 milligramsof sodium to have?10) The table values for Calories(x) and Sodium (y1) show values for all realnumbers. Explain why all real numbers would not be appropriate domains/rangesfor this situation?11) What do the residual plot values that you wrote in the table represent?12) Look at the sketch of your residual plot graph. Does it imply that a linear modelis a good fit for the data? YES or NO.13) Justify your answer to question 12 by finishing the following statements:a) A residual plot that implies a linear model exists would look b) A residual plot that implies a NON-linear model exists would look 14) Again, show you know how to interpret residual plots. Create a rough sketch ofa residual plot that would imply a Linear model is appropriate in graph 1. In graph 2,create a residual plot that implies a Non-Linear plot is probably more appropriate.Graph 1Graph 2

The TI-84 cannot do this, if you do not command it to determine a LIN REG. TI-84 Component of Assignment- Creating A Linear Regression 1) Keep your data in L1 and L2. 2) Create the LinReg in the STAT button. Before you command the calculator to CALCULATE, store the functio