Water displacement method

Reference no: EM137739

1. Some researchers have conjectured that stem-pitting disease in peach-tree seedlings might be controlled through weed and soil treatment. An experiment was conducted to compare peach-tree seedling growth with soil and weeds treated with one of two herbicides.
In a field containing ten seedlings, five were randomly selected throughout the field and assigned to receive Herbicide A. The remainder received Herbicide B. Soil and weeds for each seedling were treated with the appropriate herbicide, and at the end of the study period the height in (cm) was recorded for each seedling. The following results were obtained:

230_Confidence interval1.png

A 90% confidence interval for the difference in mean heights for the two herbicides is (0.2, 14.6). Which statement is correct?

A. The P-value for a test of the null hypothesis of equal means and the alternative of different means would be greater than 10% since the interval doesn't include 0.
B. A 95% confidence could not include zero either, since we would be even more confident of a difference in the groups.
C. Neither is correct.

2. I did an eggsperiment with a fellow instructor one day. His calculus class was studying volumes of solids by rotating curves around the x-axis. We modeled the volume of an egg as an ellipsoid, and measured eggs with calipers, using the calculus formula. Each egg was also measured for volume using a water displacement method. We wanted to know if the two methods agreed or not. The data were

964_Water displacement method.gif

The value of the test statistic for the test is
A. t = 0.975.
B. t = 0.387.
C. z = 0.975.

Reference no: EM137739

Questions Cloud

Find the standard error : The conservative degrees of freedom for the t distribution are and The standard error, conservative degrees of freedom

Difference between the t and z distributions : The correct set of hypotheses to test the effect of the bonus plan, the difference between the t and z distributions

Evaluate the standard error for the sample : The standard deviation of grade points was 0.65 and the mean was 2.89. The standard error for the sample was

Evaluate the confidence interval : The 50 members of the placebo group had blood pressure lowered by an average of 15 points with standard deviation 8 points. To analyze this information we will use a, When testing whether or not the increases in spending are different, the test is ..

Water displacement method : Each egg was also measured for volume using a water displacement method. We wanted to know if the two methods agreed or not

Evaluate the standard deviation : Evaluate the standard deviation - use the conservative value for the degrees of freedom, Assume the two groups are independent and the data are approximately Normal. Let µ 1 and µ 2 represent the mean heart rates we would observe for the entire po..

Standard deviations for first- and second-time : Standard deviations for first- and second-time and confidence interval

Test the hypotheses : The sample size n, the sample means, and the sample standard deviations for the two groups are given

Confidence interval : Do students tend to improve their SAT Mathematics (SAT-M) score the second time they take the test? A random sample of four students who took the test twice received the following scores

User Account

All Pages