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Laboratory Methods 

Overview Microscope studies Flagella experiment Laboratory math Blood fractionation Gel electrophoresis Protein gel analysis Mitochondria Concepts/ theory 
Overview Keeping a lab notebook Writing research papers Dimensions & units Using figures (graphs) Examples of graphs Experimental error Representing error Applying statistics 
Overview Principles of microscopy Solutions & dilutions Protein assays Spectrophotometry Fractionation & centrifugation Radioisotopes and detection 

Statistical tests
Tables

Selected Critical Values of the tDistributionA test is 2tailed if you ask the question, 'does population 1 differ from population 2'. Then, if the mean for population 1 is significantly greater or smaller than that for population 2, you reject the null hypothesis. If you ask simply, is the true mean for population 1 greater than that for population 2, then you reject the null hypothesis only if the experimental mean for population 1 is found to be significantly greater. It can be significantly smaller, but you weren't asking that question. That would be a onetailed test. For a twotailed test if the calculated value of t exceeds the tabled value, then report the p value in the table. For a onetailed test, the p value is divided by two. So 'p < 0.05' becomes 'p < 0.025."The table should include values for p=0.1 so that a onetailed test can be conducted at the p=0.05 level, but we never do such tests in my class, so why clutter up the table? 

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and Intended Use Visitors: to ensure that your message is not mistaken for SPAM, please include the acronym "Bios211" in the subject line of email communications Created by David R. Caprette (caprette@rice.edu), Rice University Dates 