Texas Instruments TINSPIRECX manual Different Approach to Scatterplots, Regression

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A Different Approach to Scatterplots

•Open a new Graphs page.

•From the Graph Type menu choose Scatter Plot – b34.

•Set x to be radius and y to be area.

•From the Window menu choose

Zoom–Dataand hide the entry line to gain a good view of the data points including the horizontal axis.

•Now choose Function from the Graph Type menu - b31.

•Enter f1(x)=x2.

•Now you can click and drag the quadratic curve into place to fit the data, just as you did earlier for the straight line.

Regression

Go back to the each of the scatter plots on the Data & Statistics pages in turn. From the Analyze menu choose Regression and place appropriate lines on the data.

First Steps with TI-Nspire™

Appendix: Multiple Representations

The basic quadratic ready for fitting…

… and dragged into place

What other mathematical examples lend themselves to this sort of approach?

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© 2012 Texas Instruments Education Technology

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Contents First Steps About this document Contents Appendix TI-Nspire CX Keypad Layout Memory TI-Nspire DocumentsNothing on the screen? Battery Life Charging the handheldHome Screen First Steps with TI-Nspire Tutorial 1 TI-Nspire documents Documents, Problems and Pages ScratchpadNavigating Documents First Steps with TI-Nspire Tutorial 1 TI-Nspire documents Contextual Menus Check list of some key points in Tutorial Calculator Application Basic operationsHistory Lesson Approximate CalculationsTemplates Menu of maths templatesGetting Set Document settings dialog boxEffect of changed settings Use of function notation Some AlgebraWays to define variables Lists of random integers Calculator MenuStatistical Distribution Tables Variables Linked to Documents List of defined variablesVarious text formatting Instructions Recording results Why use Notes?Making Notes Ways to split the screen You must press /e and then b Splitting the ScreenFormat sub-menu An inserted comment Use of proof template and symbols More Options from the Notes MenuInteractive Notes Use of Q+A templateAsking Questions Check list of some key points in Tutorial Graphing Graphs & Geometry Two ViewsGraphing Functions Graphing ViewGrab and Drag Practice Changing the AxesOpen-hand cursor Grabbed tick mark on the axesChanging f2 in the function history Zoom settings Grabbed-sheet iconEditing, Deleting or Hiding a Function Tracing Graphs Points and coordinatesTrace picks out significant points Points of intersectionAnalyse Graph Menu Coordinates and labelled pointsAlternative icons Transformed graph and equation Using SlidersManually Moving Graphs Sequence Plotting Check list of some key points in Tutorial Geometry View for Plane GeometryTwo Parallel Lines Drawing the base of the triangleMany options in the Construction menu What’s grabbable?Construct the Triangle Making Measurements Variables and TextMeasurement menu Storing the measurement as a variableTidying Up and Using Attributes Dynamic ChangesReady to grab a and slide it Changing the attributes of the triangleArea is now locked Unlocked/Unpinned Points B and C. Try Moving point BCheck list of some key points in Tutorial Lists & Spreadsheet Entering Data as ListsOne way to enter a formula Typical Spreadsheet Actions Using FormulaeConflict resolution Hand-made function table Capturing DataFunction Tables Simple function table Options for function tables Graph and table side by sideFrequency Charts Shoe Sizes and Hand Spans Charts with One VariableOne and Two Variable Statistics Charts for Categorical Data Pie Chart displaying categorical dataComparing Boxplots Upper quartile displayedReady to add a 2nd variable Charts with Two VariablesFitting a Line by Hand and Eye Calculated regression line Statistics Calculations menu Drawing the Regression LineGetting the Stats Dragging on the Charts Working with Frequency DataSets of statistics Effect of moving a point from here … … to hereTexas Instruments Education Technology Check list of some key points in Tutorial Measured circle Multiple RepresentationsDraw and Measure a Circle Setting up a scatter plot Data capture is under way Spreadsheet for Data CaptureTwo Scatterplots Collecting Just a Little DataGo to Town with Data Collection Fit a Straight LineLinear relationship Moving a straight line by hand Not a linear relationshipBasic quadratic ready for fitting… … and dragged into place Different Approach to ScatterplotsRegression