CHAPTER 5: HYPOTHESIS TESTING: DOES MY DATA FIT AN EXPECTED RATIO?
In this section we have included some additional examples for you to test out your understanding of the topics in this chapter. The areas each exercise covers are explained at the start of each question so that you can decide if this is a topic you would like to practice. Cross referencing to the book uses the numbers from the sections in the book. Cross referencing to material on these web pages is always indicated by a W. Throughout these sections we have highlighted the words that appear in our glossary. This is provided as part of this web site to make it easy for you to check the meaning of these terms.
If an answer is a number you should enter the value up to 2 decimal places. The computer will check your answer. If it is not correct you will be able to check the calculation to see where you went wrong. If the answer is text then having entered your answer you will be able to check our answer to see if you are correct.
In the interactive exercises we ask a series of questions about a particular undergraduate study. We then walk you through the steps you need to follow to answer each question. Where there are calculations you can check your answer, and see the calculation in full and see how to carry out these calculations using Excel, SPSS, and Minitab.
INTERACTIVE EXERCISE 1. EXAMPLE W5.1. The movement of European house dust mites (Dermatophagoides pteronyssinus) on different types of carpet.
This exercise uses data from a real undergraduate research project. The aim of the question is to test your understanding of the topics covered in 5.3 and 5.6.
INTERACTIVE EXERCISE 2. EXAMPLE W5.2. Attitudes to over the counter genetic tests.
This exercise uses data from a real undergraduate research project. The aim of the exercise is to enable you to integrate many of the topics we covered in chapters 1 to 5, as well as the summary included in appendix B Which statistical test should I choose? Although this may appear to be challenging we anticipate that if you are just dipping into this chapter you will be able to complete most if not all the questions.
INTERACTIVE EXERCISE 3. EXAMPLE W5.3. Seed dispersal in Taxus baccata (yew).
In Chapter 3 we introduced a number of different distributions including the Normal distribution and the Poisson distribution. Each distribution has a set of characteristics. For example in data with a Poisson distribution (3.5.3. iii) the mean will approximately equal the variance. To confirm that data have a particular distribution you can use the chi-squared goodness of fit test (5.1.3.). In this exercise we take you through the steps needed to confirm that your data has a Poisson distribution.
INTERACTIVE EXERCISE 4. EXAMPLE 7.1. The evolution of Littorina littoralis at Aberystwyth 2002.In Chapters 6 and 7 we introduce you to some parametric statistical tests. These tests assume that the data you are using is Normally distributed. We explain in 3.8. some of the ways to tell if your data are Normally distributed. The most comprehensive method however is described in 5.1.3 and requires the use of a chi-squared goodness of fit test. Here we provide an example of how to determine if your data are Normally distributed. The example we use is taken from Chapter 7.
