Significance of correlation co

I know the answer for the following problem is :
r=-0.69, df=10, not significant at 0.5

How do I get to that answer?

An economist is interested in studying the relationships between length of unemployment and job seeking activity among white collar workers. He interviews a sample of 12 unemployment accountants as to the number of weeks they have been unemployed (x) and seeking a job during the past year (y). Compute a Pearson’s correlation coefficient for these data and determine whether the correlation is significant.

Accountant X Y
___________________
A 2 8
B 7 3
C 5 4
D 12 2
E 1 5
F 10 2
G 8 1
H 6 5
I 5 4
J 2 6
K 3 7
L 4 1

Significance of correlation Co

See attached data file.

Use the attached CIA Economic and Demographic data report on 46 countries. Take the variables literacy rate, population, and GDP for each country, and compute the correlation among variables. In other words, find the correlation between literacy and pupulation, literacy and GDP, and population and GDP. At the 0.05 significance level, can we conclude that the correlation is different from zero for each pair of the variables ?

Please show a step by step answer especially for the test statistic used to compute the t value for the null hypothesis.

Significance of correlation co

Question # 1

If r=-0.726 and n=6, test the significance of the correlation coefficient at a=.05

Question # 2

For the conjecture “The average age of students in the class is 25”, the null hypothesis is ???

Significance of correlation co

Construct a scatter plot of the raw data. Then, run the correlation/regression program.

New Car Mileage Ratings: Listed below are combined city-highway fuel economy ratings (in mi/gal) for different cars. The old ratings are based on tests used before 2008 and the new ratings are based on tests that went into effect in 2008. Is there sufficient evidence to conclude that there is a linear correlation between the old ratings and the new ratings?

Old 16 27 17 33 28 24 18 22 20 29 21

New 15 24 15 29 25 22 16 20 18 26 19

Identify the correlation coefficient: r = __________;
Identify the CV at α = 0.05: __________

Is there significant linear correlation?: ________
How do you know? ____________________________

Significance of correlation co

A pharmaceutical company conducts a study to evaluate the relationship between length of time taking drug X and size of tumor. They enlist 2400 patients with the same type of benign tumor who have been on drug X for varying lengths of time (measured in days). They find that the longer the patient is on the drug, the smaller the patient’s tumor size (measured in volume). In fact, they report the results as r(2398) = -.21, with significance of p < .0001. What is your initial perception of this information?

What are other ways, beyond looking at the p-value alone, you could use to try to interpret what this outcome of r(2398) = -.21 tells us about the relationship between length of time taking drug X and the size of the tumor? Support your responses.