Amanda N. Wavrin Week 12

Vibrio choleraeMicroarray Presentation Assignment

Normalizing the Log Ratios for the Set of Slides in the Experiment

• Created a new excel sheet labeled scaled_centered
• Copy and pasted the spreadsheet into the new scaled_centered sheet
• Inserted two rows at the top below the headers
• Added headers "Average" to cell A2 and "StdDev" to cell A3
• Computed the average log ratio using the equation =AVERAGE(B4:B5224)
• Computed the StdDev using equations such as =STDEV(B4:B5224)
• Now will do the scaling and centering using these found values
• Added "scaled_centered" columns after each column
• Used the equation =(B4-$B$2)/$B$3, =(D4-$D$2)/$D$3, and so on

Performing Statistical Analysis on the Ratios

• Added new worksheet labeked statistics
• Used the new worksheet to compute the average log fold change for the replicates for each patient
• Calculated the averages of the averages
• Computed a T statistic to tell us whether the average log ratio is significantly different than 0