The field of statistics provides methods for collecting, summarizing, analyzing data, and interpreting analysis results. You can use data statistics to describe data and make inferences. Then these inferences can be used to improve the process and product。
Minitabprovides many statistical analysis methods, such as regression, analysis of variance, quality tools, and time series. The built-in graphics can help you visualize your data,
And verify your analysis results. In Minitab, you can also display and store statistical data and diagnostic metrics.
In this chapter, you can evaluate the number of late and delayed orders and test whether there is a significant statistical difference in delivery time between the three shipping centers significance。
Summarize the data
Descriptive statistics summarize and describe the significant features of the data. Using descriptive statistics to determine how many book orders were delivered on time by each shipping center, How many orders are overdue and how many are delayed from the beginning.
Display Descriptive Statistics
1. Open sample data shipment data. MTW。
2. Select Statistics>Basic Statistics>Display Descriptive Statistics。
3. In the variable, enter the number of days。
4. In the group by variable (optional), enter the center state。
For most Minitab commands, simply complete the main dialog box to execute the command. You can usually use sub dialog boxes to modify the analysis or display additional output
（Like graphics）。
Image 1: Display descriptive statistics
5. Click Statistics。
6. Uncheck the first Quartile, median, third Quartile, N non missing and N missing。
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7. Selected N Total。
Image 2: Display Descriptive Statistics - Statistics
8. Click OK in each dialog box。
Note: The changes you make in the Statistics Quantum dialog box will only affect the current session. To change the default options for future sessions, select File>Options. Expand a single command and select Show Descriptive Statistics. Select the statistics you want to display. When you open the Statistics Quantum dialog box again, it will display your new options.
Image 3: Data
Note: Any output can be sent to the locally installed version of Word, PowerPoint, or Companion by Minitab. To send a single graph or table, right-click on the output and select the program to send the output to. To send the content of the entire output tab, right-click the output title above the line at the top of the pane.
Interpreting results
The output pane will display the results for each center separately. Within each center, the quantity of delayed, overdue, and on time deliveries can be found in the total column。
• The Eastern Shipping Center has the highest number of delayed deliveries (8) and overdue deliveries (9)。
• The number of delayed deliveries (6) and overdue deliveries (6) in the central shipping center are in second place。
• The western shipping center has the lowest number of delayed deliveries (3) and no overdue deliveries。
The output also includes the mean delivery time (days) of each center, standard error of the mean, standard deviation, minimum and maximum values. These statistics are useful for delay Delivery does not exist.
