2013年6月30日星期日

Statistics 3: Hypothesis between categorical variables

CHI SQUARE TEST

CHI-SQUARE GOODNESS-OF-FIT TEST (only one category)

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CHI-SQUARE TEST OF INDEPENDENCE (two categories)

Condition:

1. Use only absolute frequencies (not percentage) in the calculation.

2. Make sure that each individual is included in only one category

3. Check that all expected frequencies are at least 5.

2013年6月26日星期三

Statistics 6: Non parametric statistics

When the data is about small sample or there is no homogeneity of variance between groups.

1. CHI SQUARE 

condition: one sample one test

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X2(2)=20.6, p<0.05

1. df=r-1

2. p value

3. two tailed test only

p.188-189

Statistics 5: Hypothesis test between numerical variables

1. BIVARIATE CORRELATION

To test correlation ship between two variables

2. REGRESSION EQUATION

Line of best fit and Standard error of estimates

Y'=bX+a

Multiple regression: when you determine to include multiple independent variables, be sure of the correlation between each independent variable and dependent variable, and the independence between every pair of independent variables.

2013年3月3日星期日

Excel

I. 选取图表类型

柱形图:用于比较

条形图:类型名称过长时

折线图:趋势。需注意时间序列等值连续

饼图:百分比

环形图:一到两个不同百分比比较

条形堆积图:百分比比较

XY分散图和气泡图:两到三个序列间相关关系

趋势线可初步显示相关性

II. 动态图表

参数表,源数据表,数据透视表

III. 图表美化和误差

使用图表重叠,填充和透明度美化

使用标注说明

注意图表长宽和数值区间

0值填充,隐藏数据不显示

IV. 特殊图表制作请再参阅