Stats Help for College-level Students

Statistics

Hypothesis testing questions

Statistics

Hypothesis testing questions.

Statistics

Regression questions

Set up the hypotheses to see if there is a difference in the number of purchases made on-line by women for the three age groups. Perform the Kruskal- Wallis test at the 0.05 level of significance. What can you conclude? Find the equation of the regression line for the data.

18.6 A business that is interested in starting an on-line shopping service is interested in finding out whether or not there are differences in how women shop on-line. They are interested in capturing people who are already connected to the Internet, so they run a Web. based survey. They ask respondents how many purchases they h ...continues

probability

Solving probability questions

Statistics: geological study and large elevator

1. A geological study indicates that wells drilled in a certain area should strike water with probability 0.2. Find the probability that: a) first strike of water comes in the 3rd well drilled b) 3 strikes of water in 5 drills 2. A large elevator has a max weight limit of 10,000 lbs. Suppose a load has 45 boxes. This has a ...continues

Statistics Cases

a) What is the response variable and what is the factor? b) Ho many levels of the factor are being studied? c) Is there any difference in the average time to failure of the disks from the 3 different suppliers? If so, which ones are different? d) What is your recommendation to the company and why?

Working with the Chi-Square Procedure.

Suppose that you want to decide whether the distribution of primary heating fuel of occupied housing units built after 1974 differs from that of all occupied housing units. To help you decide, you take a random sample of n housing units built after 1974 and obtain a frequency distribution of their primary heating fuel. The p ...continues

Calculations of mean, median, and mode.

Calculate mean, median, and mode. Graph the data and locate the averages. See attached file for full problem description.

Using the probability density function to find the cumulative distribution function of an exponentially distributed random variable.

You are told that the continuous random variable X is exponentially distributed with parameter a (a > 0). A standard result then says that the probability density function of X is (see attachment) f(x) = aexp(-ax) for x > 0. Use this to prove that the corresponding cumulative distribution function F(x) (sometimes referred ...continues