Preface A Simple Experiment in Pipetting Collecting Data Standardizing Pipettes Purpose and Design Opening MINITAB Arranging a Random Sequence Collecting and Sorting the Observations Pictorial Display Descriptive Statistics Summary Further Notes More About Random Numbers How to Condense the Bulkiness of Data Early Steps Histograms, or Bar Charts From Histogram to Normal Distribution Areas Under a Normal Distribution Curve Sample and Population Summary Further Notes Standard Deviation Variance Standard Deviation and Normal Distribution Precision and Accuracy Are Those Differences Significant? Signposting for Different Types of Data One-way Analysis of Variance Which Pipette is Different from Which? Testing for Normality Summary Further Notes Random-sampling Fluctuations Null Hypothesis More About Measurement Differences Internal Anatomy of the 135 Pipetting Results Summary Statistics Two-way Analysis of Variance Two-way ANOVA on Fewer Data Student's t-Test Summary Awkward-Measurement Data Awkwardness in Measurement Data Standard Deviations Grossly Different Skewed Distributions Data Sets with Indefinite Values Summary How to Deal with Count Data From Bacterial Colonies to Umbrellas Left on Buses Total Cell Counts as a Worked Example Poisson Distribution for Interpreting the Helber Data Changeable Shape of the Poisson Distribution Standard Error and Confidence Intervals of Counts Analysis of Differences between Counts by Chi-square Application of ANOVA Where Poisson Fails to Rule Summary Further Notes Formula for the Poisson Distribution Insights into Chi-square Chi-square for Exploring Conformity to Poisson How to Deal with Proportion Data Developing a Sense of Proportion Large-group Proportion Data Small-group Proportion Data Are Those Ampoules Sterile? Most Probable Numbers in Microbial Counting Is that Inheritance Mendelian? Summary Further Notes Chi-square for 2 X 2 Contingency Table Formula for the Binomial Distribution Power Calculations for Group Size Correlation and Regression Preliminary Signposting Correlation of Normally-distributed Variables Rank Correlation Linear Regression Additional Statistics of Linear Regression Summary Dose--Response Lines and Assays Dose--Response Interpolation Assay Four-Point Parallel Line Assay Quantal-Response Assay Summary References Additional Reading Appendices: Statistical Tables and Figures A1 Most probable numbers from three successive tenfold dilutions, five tubes of each A2 Most probable numbers from three successive tenfold dilutions, eight tubes of each A3 Significance of differences between proportions Index