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Explain which test you would use to analyze the data. (You may get a little partial credit if you list the variables and type of each variable.)   You want to know whether a piece of bare copper wire in a bird bath will release enough dissolved copper to kill mosquito larvae. You go to a birdwatchers’ club and find 32 people who each have two bird baths in their yard. You have them randomly choose one bird bath to put a piece of copper wire into. After a month, you go to each bird bath and count the number of mosquito larvae. Which test should you use?  

In a one-way ANOVA, when the null hypothesis that the means are all the same is rejected using the ANOVA, we can then conclude that all the means are different from one another.

A researcher has calculated a 90% confidence interval for the mean weight in grams (µ) of a newborn baby and found it to be 2934 ± 222 grams. (Note that this means the the confidence interval is 2712 < µ < 3156). Determine whether the following statements is true or false.   If we took many additional random samples of the same size and from each computed a 90% confidence interval for µ, approximately 90% of these intervals would contain µ.

Is there a significant relationship between the number of stamens and the number of carpels?  Explain (using a hypothesis test).

View the three type of dose-response curves below – the top on is (a), the middle is (b) and the last one is (c). Which graph would most likely correspond to how a test on BPA (an endocrine disruptive chemical) would look like? 

Which of the following values of r indicates the most strongest relationship between two quantitative variables?

The   _______ the p-value, the stronger the evidence against the null hypothesis provided by the data.

The sum of the ranks for the three groups are: Cylinders Rank Sum 4 16 6 45 8 44   Find the value of the test statistic, H. What is the p-value of the test? What is the conclusion for the hypothesis test?

Fourteen mature flowers of a particular species were dissected, and the number of carpels and stamens present in each flower were counted.   Carpels (x) 27 31 28 22 26 29 30 30 24 25 22 29 28 25 Stamens (y) 52 68 70 45 61 50 56 65 43 37 36 74 38 35   Here is a graph of the data, along with the line of best fit (LSRL).   Use this data for the next three questions.

(same data as previous problem) The manager of a soda bottling plant is interested in comparing the performance of two bottling machines, the old machine and a new machine that has just been purchased. For each machine she selects 10 one-hour periods at random and records the number of crates completed in each hour. The table below gives the results. New 78 87 79 82 87 81 85 80 82 83 Old 74 77 78 70 87 83 76 78 81 76   (b)     Give a 90% confidence interval for the difference in the two means. (Don’t forget the sentence.)