Measures of Center
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Measures of Center MAFS.7.SP.2.3 Informally assess the degree of visual overlap of two numerical data distributions with similar variabilities, measuring the difference between the centers by expressing it as a multiple of a measure of variability.
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Measures of Center. MAFS.7.SP.2.3 Informally assess the degree of visual overlap of two numerical data distributions with similar variabilities, measuring the difference between the centers by expressing it as a multiple of a measure of variability. - PowerPoint PPT Presentation
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Measures of Center
MAFS.7.SP.2.3 Informally assess the degree of visual overlap of two numerical data distributions with similar variabilities, measuring the difference between the centers by expressing it as a multiple of a measure of variability.
Do 5th graders and 7th graders spend the same amount of time studying
math?
In this lesson you will learn to compare two data sets by looking at their means and mean absolute deviations.
http://www.google.com/imgres?imgurl=http%3A%2F%2Fbestclipartblog.com%2Fclipart-pics%2F-math-clipart-3.gif&imgrefurl=http%3A%2F%2Fbestclipartblog.com%2F22-math-clip-art.html%2Fmath-clipart-3&h=362&w=303&tbnid=TKgA6t-bAaqTcM%3A&zoom=1&docid=0NriKZKIw9BiqM&ei=N5OpU7KZB9HQsQTgnIDYCA&tbm=isch&ved=0CFEQMygVMBU&iact=rc&uact=3&dur=4101&page=2&start=8&ndsp=17
Mean – the sum of a set of numbers divided by the number of elements in the set. Also known as average.
https://www.google.com/search?q=mean+median+mode+clip+art&rlz=1C1FLDB_enUS514&espv=2&biw=994&bih=611&tbm=isch&imgil=Nr11A8HHfg39dM%253A%253Bhttps%253A%252F%252Fencrypted-tbn1.gstatic.com%252Fimages%253Fq%253Dtbn%253AANd9GcTKv2IPwbIZGTzWpNcq3_01yh4n2QbDFtKB77bmRVLr5p1B_4Sbvw%253B596%253B413%253Bcb7wjLs050jcTM%253Bhttp%25253A%25252F%25252Fserchomeschool.wordpress.com%25252F2014%25252F01%25252F02%25252Fmean-median-and-mode-science-and-math-in-action-pre-class-materials-class-3%25252F&source=iu&usg=__wj6cesAm8nHquDRb2AoBrk-iT-4%3D&sa=X&ei=rpOpU429N8LJsQSlq4LwBQ&ved=0CB8Q9QEwAA
Mean Absolute DeviationThe average distance between each data
point and the mean.
https://gcps.desire2learn.com/d2l/lor/viewer/viewFile.d2lfile/15534/6719/M.A.D.Cartoon.png
Time Spent Studying Math in 5th grade (per week in minutes)
0 30 60 90 120 150 180
Time Spent Studying Math in 7th grade (per week in minutes)
0 30 60 90 120 150 180
Dot Plot comparing 5th grade and 7th grade math study time
5th Grade Study Time
0 60
30 60
30 60
30 90
60
60 Total = 480
Mean
480 10 = 48 minutes
5th Grade Study Time
0 – 48= |-48|
60-48 = 12
30-48= |-18|
60-48 = 12
30-48= |-18|
60-48 = 12
30-48 = |-18|
90 -48=42
60-48= 12
60-48= 12 Total = 204
Mean Absolute Deviation
204 10 = 20.4 minutes
20.4 minutes is the average distance away from the mean.
7th Grade Study Time
60 150
90 150
120 180
120 180
120
120 Total = 1,290
Mean
1290 10 = 129 minutes
7th Grade Study Time
60 -129 = |-69|
150-129=21
90-129 =|-39| 150-129= 21
120-129= |-9| 180-129 = 51
120-129= |-9| 180-129= 51
120-129= |-9|
120-129= |-9| Total = 288
Mean Absolute Deviation
288 10 = 28.8 minutes
MAD – what does it mean?
The higher the MAD, the greater variability there is in the data (variability is how spread out or how clustered a group of data is).
High variability means the data is really spread out.
Low variability means the data is really close together. How does this apply to our
data?
