Statistical Thinking

(uit elementary statistics)

 

Prepare

1. Context
What do the data mean?
What is the goal of study?
2. Source of the Data
Are the data from a source with a special interest so that there is pressure to obtain results that are favorable to the source?
3. Sampling Method
Were the data collected in a way that is unbiased, or were the data collected in a way that is biased (such as a procedure in which respondents volunteerto participate)?
I

Analyze

1. Graph the Data
2. Explore the Data
Are there any outliers (numbers very far away from almost all of the other data)? What important statistics summarize the data (such as the mean and standard deviation described in later)?
How are the data distributed?
Are there missing data?
Did many selected subjects refuse to respond?
3. Apply Statistical Methods Use technology to obtain results.
I

Conclude

1. Statistical Significance
Do the results have statistical significance?
Do the results have practical significance?

Although the mean weight loss of 2.1 kg is statistically significant, it does not have practical significance. The statistical analysis suggests that the weight loss program is effective, but practical considerations suggest that the program is basically ineffective.

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