R programm, statistics, Basic Statistics

1. Generate a large dataset ( at least 1000 observations) µ with a known mean, µ between 20 and 40 and variance s = 9 using rnorm(). identify it as D. Use the functions mean() and var() to get the mean and vaiance of the sample.
2. Use t.test(D, mu=0) to check if the mean of your realizations, ¯x is signi?cantly
different from zero, from µ1, and from (µ0:1).
3. produce a histogram for D with vertical lines at the 0.25
th
and the 97.5
th
quantiles.
4. generate 10 samples of 20, S1 .....S10 with random means using S1<- rnorm(20,runif(1,min=0,max
= 80)), then calculate means and variances for each.
5. Use t.test(D, S1) to check if the sample means for S1 .....S10 are likely to have come
from the same population as the large distribution D. This Stat Trek webpage is a
good source. You should be using 2-tailed tests.
6. Explain the difference between a one-tailed test and a two-tailed test.
7. Create two variables, x and y, where y is a deterministic linear function of x. Show
the formula you used.
8. Generate a plot of y against x.
9. Calculate the correlation between y and x.covariance of y and x.
10. Create a new variable, yRan, that is like y except that it contains some random noise.
11. Calculate the correlation between yRan and x and the covariance of yRan and x.
12. Add more noise to yRan. Calculate the covariance of yRan and x and the Pearsonian correlation coef?cient. State how adding more noise affects the correlation
coef?cient.
13. Conduct the following experiment. Start with a deterministic function as in part 8
with a positive slope. Add some noise. Now systematically reduce the slope from
positive to negative, taking care to make quite a few observations near zero. Keep
the noise parameters constant. Make a table showing the slope vs the correlation
coef?cient.
14. Plot the slope vs the correlation coef?cient from the previous question and say what
you learn from the exercise.
Posted Date: 3/6/2012 8:23:46 AM | Location : United States







Related Discussions:- R programm, statistics, Assignment Help, Ask Question on R programm, statistics, Get Answer, Expert's Help, R programm, statistics Discussions

Write discussion on R programm, statistics
Your posts are moderated
Related Questions
#questKody Corporation uses a job-order costing system with a plantwide overhead rate based on machine-hours. At the beginning of the year, the company made the following estimates

how to find 1st quartile from the graph of more than ogive type, please reply me with an example

Classification feature of Accounting Transaction. Under the classification accountant posts the entries into their respective ledgers in the Accounts Books. Every Account entry

in my home work it is a balance sheet 12/31/2010 12/31/2009 accounts recievable 8000 10000 below it has letter a b c d e f-k wanting the letter with the explaination a

It is a sunny Tuesday afternoon in the perfectly manicured harbourside city of Sydney. Dressed in your favourite pin stripe Gucci (Black Label thank you very much) and those hand c

Shafts are cut to length by two machines, A and B. Each machine cuts 50 percent of all shafts in approximately the same amount of time. Machine A's shafts are all good, but Machine

The research should be Quantitative Research: A means for testing objective theories by examining the relationship among variables. These variables can be measured and analyzed

how to draw less than ogive

How do you think the banking sector is going to get impacted?   Manager 1: The impact of the shift to IFRS is going to be much higher in the banking sector. This impact woul

Depreciation during the financial year  The Resources which are bought during the economical season and its determined that the Depreciation will be incurred on them @ 10% PA it