Parents are frequently concerned when their child seems slow to begin walking (although when the child finally walks, the resulting havoc sometimes has the parents wishing they could turn back the clock!). The article “Walking in the Newborn” (Science, 176 [1972]: 314–315) reported on an experiment in which the effects of several different treatments on the age at which a child first walks were compared.
Children in the first group were given special walking exercises for 12 minutes per day beginning at age 1 week and lasting 7 weeks. The second group of children received daily exercises but not the walking exercises administered to the first group. The third and fourth groups were control groups: They received no special treatment and differed only in that the third group’s progress was checked weekly, whereas the fourth group’s progress was checked just once at the end of the study.
Observations on age (in months) when the children first walked are shown in the accompanying table. Also given is the ANOVA table, obtained from the SPSS statistical software package.
Analysis of Variance
- a. Verify the entries in the ANOVA table.
- b. State and test the relevant hypotheses using a significance level of 0.05.
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Chapter 15 Solutions
Introduction To Statistics And Data Analysis
- 1. In the book Design and Analysis of Experiments, 8th edition (2012, John Wiley & Sons), the results of an experiment involving a storage battery used in the launching mechanism of a shoulder-fired ground-to-air missile were presented. Three material types can be used to make the battery plates. The objective is to design a battery that is relatively unaffected by the ambient temperature. The output response from the battery is effective life in hours. Three temperature levels are selected, and a factorial experiment with four replicates is run. The data are as follows: Table 11.(a) Test the appropriate hypotheses and draw conclusions using the analysis ether either firing temperature or furnace position affects the baked density of a carbon anode. The data are as follows: Table 12.(a) State the hypotheses of interest. (b) Test the hypotheses in part (a) using the analysis of variance with a = 0.05. What are your conclusions? (c) Analyze the residuals from this experiment. (d)…arrow_forwardA sample of men and women who had passed their driver's test either the first time or the second time were surveyed, with the following results: Results of the driving testGender First time Second timeMen 126 211Women 135 178a) Do these data suggest that there is a relationship between gender and the passing of their driver’s test from which the present sample was drawn? Let alpha=.05arrow_forwardIn this study, ten combat veterans undergoing treatment for PTSD were randomly sampled from a local VA hospital in a study designed to test the efficacy of an anti-anxiety medication in reducing the symptoms of PTSD. Based on clinical animal trials, the researchers predict that the drug should reduce symptoms. t= 1.63, df=9, p=0.064, d= 0.529. Before: M= 48.100, SD=1.370, SE=0.433 After: M= 47.000, SD= 1.491, SE= 0.471 My hypotheses are; H0: μbefore ≤ μafter. H1: μbefore > μafter A. State your findings in APA format: B. How would you explain these findings to someone who has never taken a statistics class? In other words, use clear direct, non-jargon language to explain the results:arrow_forward
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- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL