EQ: How can we summarize and compare data? MM1D3a Monday – 8/29/11 Math 1: Unit 1 – Day 5

The data below represent the grades of students in an Algebra 1 class: Reset your calculator by hitting [on] and [clear] at the same time Hit [data] and type the data into list L1 Hit [2 nd ][data] and choose 1:1-Var Stats 1) Mean, Median, Q1, Q3, etc

The data below represent the grades of students in an Algebra 1 class: Mean ( ): _________ Median (2nd Quartile): ________ Mode: _______ Lower Extreme: ______Upper Extreme: _______ 1st Quartile: _______3rd Quartile: _______ Video Tutorial 1) Mean, Median, Q1, Q3, etc Min Q1 Median Q2 Q3 Max

2) Mean Absolute Deviation Find the mean Find the distances from the mean Find the average of the distances Video Tutorial

2) Mean Absolute Deviation Find the mean oHit [data] and type data into L1 oHit [2 nd ][data] and choose 1:1-Var Stats oThe mean is 58

2) Mean Absolute Deviation Find the distances from the mean of 58 oHit [data] and Arrow over to L2 oHit [data] and arrow to FORMULA oChoose 1:Add/Edit Frmla oHit [data] and choose L1 then type -58 [enter] oType the absolute values of L2 into L3

2) Mean Absolute Deviation Find the mean of the distances in L3 oHit [2 nd ][data] and choose 1:1-Var Stats oMake sure L3 is highlighted oThe average distance from the mean is 15.5 oThis is the mean absolute deviation

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Class 1 We know the median is 70 We know the interquartile range is 15 Here are the possibilities

Class 2 We know the median is 75 We know the interquartile range is 12 Here are the possibilities

Class 1 and Class 2 Class 2 Class 1 Q3 zone We know that both classes had the same 3 rd quartile score Where is it possible that the 3 rd quartile could be the same? From where to where do the Q3 zones overlap? It looks like 75 to 85

The answer is D. 4)

Calls made during June: 11, 15, 10, 37, 17, 14, 9, 15 What is the mean (absolute) deviation for calls made in June? 5) Calls made during July: 13, 9, 16, 8, 17, 20, 8, 13 What is the mean (absolute) deviation for calls made in July? 6) The mean absolute deviation tells you how variable the data is. A bigger deviation means the data is more spread out. During which month were the calls more variable? 7) The June calls were more variable based on the higher mean absolute deviation.