Independent random samples of 36 and 50 observations are drawn from two quantitative populations, 1 and 2, respectively. The sample data summary is shown here:

Do the data present sufficient evidence to indicate that the mean for population 1 is smaller than the mean for population 2? Use the p-value approach and the critical value approach and explain your conclusion.

Problem #2

A researcher believes she has designed a keyboard that is more efficient to use than a standard keyboard. In order to help decide if this is the case, typing speeds were taken for 8 different people on each keyboard. The lengths of time, in minutes, for each of the people to type a pre-selected manuscript are listed below. Assume the two population distributions are normal. Use the data to determine if the original keyboard yields slower times. Use a significance level of  = 0.05.

Person Original New
1 15 12
2 9 8
3 17 15
4 10 8
5 9 5
6 4 4
7 30 25
8 29 21

Problem #3

Assume that the population distributions of times (in minutes) for two different skiers to
race the same course are normal with equal variances. Two random samples, drawn
independently from the populations, showed the following statistics:

Construct and interpret a 95% confidence interval for the true difference in average time of skiers to race the same course.

Independent random samples of 36 and 50 observations are drawn from two quantitative populations, 1 and 2, respectively. The sample data summary is shown here:

... One Sample Tests of Hypothesis According to news reports, Las ... Here we are testing whether the population mean number of ... is one-tailed and is a upper tail test. ...

... intervals for samples requiring a one sample t-tests. ... The first step in the hypothesis test is to calculate ... mean number employed in the population from which ...

...Hypothesis test, critical values for rejection You have a sample size of 120 and the population standard deviation of 20. You are testing the null hypothesis...

... Lower-Tail Test Tests if a mean or proportion is ... experience, you can assume that the population standard deviation is ... Decide what type of test it is, and what ...

... When would you use a two population test with a large ... When testing two populations and one sample's size is small ... What is a test of a proportion and give an ...

... Use the standard hypothesis testing procedure. ... This is an example of a hypothesis test for a population mean. The confidence level for this test is 95%. ...

Hypothesis testing of Population proportion:Five step method. Hypothesis test for a population proportion A recent study at a local college claimed that the ...

... b. If the population standard deviation is Ï = 10, is the sample ... Again, assume a two âtailed test with Î± = .05. The null hypothesis tested is. ...