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Transcript of Scatter Plots
Scatter PlotsBy Rach and Jess 1Australian CurriculumUse scatter plots to investigate and comment on relationships between two continuous variables.Using authentic data to construct scatter plots, make comparisons and draw conclusions.
2DeclarativeA scatter plot is used to identify if there is a positive or negative relationship or no relation between a pair of variables.Tables and graphs can be used to interpret bivariate data.A line of best fit is used to identify if there is a positive or negative relationship between two variables.3ProceduralGather and analyse data for a pair of variables i.e. hand span and foot length.Record and plot data found on a graph (scatter plot).Use a line of best fit to identify a positive or negative relationship between variables.Manipulate and interpret bivariate data in tables and graphs.4What is a Scatter Plot?Show how two variables relateStrong relationshipNegative relationshipUnrelated
5What do you need?A data table with recorded variables
6What do you need?Appropriate table to fit-in data with labelled axis
7What next?Plot the points
8Analysis the dataIs there a line of best fit (linear line)?What is the relationship?What is this data telling us?
9Graphics CalculatorStrengths Accurate scatter plot with data inputAccessible in classroomsLM able to backtrack on calculator to see where students may have made mistakesX and Y intercepts automatically calculatedWeaknessesStudents do not have to set up the graph up or set the minimum or maximum for X and Y axesLine of best fit automatically calculated10Graphics CalculatorOpportunitiesTo extend students abilities to use a graphics calculatorTime savingPossible to implement in an examThreatsSimple data error entry could hinder results and accuracy11Quality Basics: The scatter plotStrengthsPositive, negative, curvilinear, no correlationIndependent and dependant variables explanations Specific point locations Prediction of particular points based on linear lineRules When Y becomes larger X becomes _______WeaknessesBrief overview possible for revisionDoes not give explanations of definitions of key mathematical terminologyDoes not provide teacher with formative feedback students may guess answers until correct answer is reached12Quality Basics: The scatter plotOpportunitiesUse for introduction of scatter plots or use for revisionThreatsInternet or server failStudents accessing other sites off task behaviour13Build a scatter plotStrengthsAutomatic calculation of means and standard deviationsAsks question are the two variables related Ability to change number of cases and correlation coefficient (strength)Linear relationships clearly seen by using line of best fitWeaknessesNo formula provided for mean or standard deviation
14Build a scatter plotOpportunitiesTo extend student knowledge on standard deviation Students to plot own pointsOption to display gridlines, ticks for each variable and means for X and YUsing ITC in the classroomThreatsInternet or server failStudents accessing other sites off task behaviour15Yeah, we are finished nowJohn, do you have anything to add?
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