2.  Range  Standard deviation  Variance  Using Excel to calculate them 2

3.  Label everything  One graph communicate one idea  Keep things balanced  Simple is best  A picture is worth a thousand words 3

4.  Frequency distribution is a method to represent the frequency of certain scores.  When you have a data set, such as a testing scores,  Class intervals  Number of intervals: 5, 10, 20  Value of interval=range/number of intervals 4

5.  50 scores  Set class intervals  Create a histogram using your hand  Using Excel to do that Score 47 2 44 41 7 6 35 38 35 36 10 11 14 30 32 33 34 32 31 15 16 17 16 15 19 18 16 25 26 27 29 28 29 27 20 21 24 23 20 21 20 5

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7.  First, define your bins  The starting point of a bin  Data analysis Toolpak  histogram 7

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9.  Skewness  Measure of the lack of symmetry of a distribution  mean>median>mode  positively skewed  mean<median<mode  negatively skewed 9

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11. Median for frequency distributions: N=total number of respondent (n=1414), If n=even number, n/2=707, if n= odd, (n+1)/2. So in fy column, 707 fits to 717 which has 3 siblings, so median=3. Or in c%, 50% fits to 63.2%, which is 3 siblings 11

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13.  Kurtosis: the degree of peakedness or flatness of a probability distribution 13

14.  Variability (S-p97-Fig 4.14) 14

15.  Excel: SKEW() and KURT()  Skewness characterizes the degree of asymmetry of a distribution around its mean. Positive skewness indicates a distribution with an asymmetric tail extending toward more positive values. Negative skewness indicates a distribution with an asymmetric tail extending toward more negative values.  Kurtosis characterizes the relative peakedness or flatness of a distribution compared with the normal distribution. Positive kurtosis indicates a relatively peaked distribution. Negative kurtosis indicates a relatively flat distribution. 15

16.  From General Social Survey 2010, we reported the number of children showed in the subsample of male and female respondents.  Create a histogram using your hand  Using Excel to do that  Mean, mode and median  Skewness (for more details on how to calcualte skewness, http://www.tc3.edu/instruct /sbrown/stat/shape.htm) 16 # of ChildrenMalesFemales 09492 15272 271127 34791 43038 5 or more3327 Total(N)327447