mathstatistics
posted by Stephanie .
18) Which of the following is the most significant result?
A) P<.001
B) P<.005
C) P=.05
D) P>.05
Okay, I have the answer key and know the question is A, but I always thought that if the P value is greater than .05 than it IS considered significant and you can reject your null hypothesisam I wrong??
19) Also somewhat of a smilar question:
Which of the following is the most significant result?
A) t9df=2.538 for a 1sided t test
B) t15df=2.538 for a 2 sided ttest
C) t26df= 2.538 for a 1sided t test
D) t49df= 2.538 for a 2 sided ttest
I have the same problem here, the first multiple choice letter that I rejected (choice C) was the right answer?!?!

You can reject Ho if p ≤ .05, which means that the results you have found would happen by chance 5% of the time or less. P > .05 means that there is a greater than 5% probability that the results were due to chance. Under those conditions, I would not reject the Ho.
Since I have not worked in the area for some time, for your last question, I searched Google under the key words "ttest significance onetailed 'degrees of freedom'" to get these possible sources:
http://www.psychstat.missouristate.edu/introbook/sbk25.htm
http://www.bized.co.uk/timeweb/crunching/crunch_experiment_reviewb.htm
http://books.google.com/books?id=2oEQyOIyCbUC&pg=RA1139PA2&lpg=RA1139PA2&dq=%22t+test%22+significance+%22one+tailed%22+%22degrees+of+freedom%22&source=web&ots=hJ038C041Z&sig=KfJKzwtnGcQEtpchFKHTdV13Mio&hl=en
http://www.bized.co.uk/timeweb/crunching/crunch_experiment_reviewb.htm
http://books.google.com/books?id=2oEQyOIyCbUC&pg=RA1139PA2&lpg=RA1139PA2&dq=%22t+test%22+significance+%22one+tailed%22+%22degrees+of+freedom%22&source=web&ots=hJ038C041Z&sig=KfJKzwtnGcQEtpchFKHTdV13Mio&hl=en
In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.
I hope this helps. Thanks for asking.