Hypotheses testing - section 1 by Daniela Stanescu https://padlet.com/dstanescu63/jbuesm7i1jlq Made with good vibes en-us 2018-11-20 23:20:50 UTC 2023-06-14 13:35:45 UTC hello@padlet.com Group 1 dstanescu63 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560211 Question 1. 
Suppose that we want to test the hypothesis with a significance level of .05 that the climate has changed since industrialization.  Suppose that the mean temperature throughout history is 50 degrees.  During the last 40 years, the mean temperature has been 51 degrees. Suppose the population standard deviation is 2 degrees and that the population is normally distributed.  What can we conclude?   

a)    State the hypotheses
b)    State the level of significance and construct the critical interval
c)    Calculate the test statistics
d)    Make a decision
e)    State a conclusion

Question 2.
In testing hypotheses, the researcher initially assumes: 

a)the alternative hypothesis is true.
b) the null hypothesis is true
 c) errors cannot be made
 d) the population parameter of interest is known 



 

]]> 2018-11-20 23:22:30 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560211 Group 2 dstanescu63 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560322 Question 1.
An automobile manufacturer recommends oil change intervals of 3,000 miles. To compare actual intervals to the recommendation, the company randomly samples records of 50 oil changes at service facilities and obtains sample mean 3,752 miles. It is known that the population standard deviation is 638 miles. Determine whether the data provide sufficient evidence, at the 5% level of significance, that the population mean interval between oil changes exceeds 3,000 miles.

a)    State the hypotheses
b)    State the level of significance and construct the critical interval
c)    Calculate the test statistics
d)    Make a decision
e)    State a conclusion

Question 2.
If a business researcher has a new theory about buying habits of consumers and wants to test it, the new theory usually is formulated into the: 

a) null hypothesis
 b) alternate hypothesis
 c) critical value
 d) substantive hypothesis 



 

]]> 2018-11-20 23:23:38 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560322 Group 3 dstanescu63 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560480 Question 1.
A medical laboratory claims that the mean turn-around time for performance of a battery of tests on blood samples is 1.88 business days. The manager of a large medical practice believes that the actual mean is larger. A random sample of 17 blood samples yielded mean 2.09 and sample standard deviation 0.13 day. Perform the relevant test at the 10% level of significance, using these data. Assume the population of turn-around times is normally distributed.
a)    State the hypotheses
b)    State the level of significance and construct the critical interval
c)    Calculate the test statistics
d)    Make a decision
e)    State a conclusion

Question 2.
The rejection and non rejection regions are divided by the: 

a) rejection value
b) dividing point
c) critical value
 d) point of no return 



]]> 2018-11-20 23:24:54 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560480 Group 4 dstanescu63 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560606 Question 1.
A grocery store chain has as one standard of service that the mean time customers wait in line to begin checking out not exceed 2 minutes. To verify the performance of a store the company measures the waiting time in 30 instances, obtaining mean time 2.17 minutes with standard deviation 0.46 minute. Use these data to test the null hypothesis that the mean waiting time is 2 minutes versus the alternative that it exceeds 2 minutes, at the 10% level of significance. Assume the population of waiting times is normally distributed.
a)    State the hypotheses
b)    State the level of significance and construct the critical interval
c)    Calculate the test statistics
d)    Make a decision
e)    State a conclusion

Question 2.
When a true null hypothesis is rejected, the researcher has committed a: 

a) Type II error
 b) Type I error
 c) rejection error
 d) error in judgment 



]]> 2018-11-20 23:25:45 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560606 Group 5 dstanescu63 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560680 Question 1.
Authors of a computer algebra system wish to compare the speed of a new computational algorithm to the currently implemented algorithm. They apply the new algorithm to 51 standard problems; it averages 8.16 seconds with standard deviation 0.17 second. The current algorithm averages 8.21 seconds on such problems. Test, at the 1% level of significance, the alternative hypothesis that the new algorithm has a lower average time than the current algorithm.
a)    State the hypotheses
b)    State the level of significance and construct the critical interval
c)    Calculate the test statistics
d)    Make a decision
e)    State a conclusion

Question 2.
Whenever hypotheses are established such that the alternative hypothesis is ">", then the test is a: 

a) Type I test
b) two-tailed test
 c) right-tailed test
 d) Type II test 



]]> 2018-11-20 23:26:28 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306560680 group members https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306845749 DIVAM JOSHI=300984102
PUSHPINDER SINGH=300981979
SIDDARTH PATHANIA=300959862
SAHIL JAGGA=300981952


]]> 2018-11-21 20:32:43 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306845749 Group 4; Gagandeep Singh https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306846767 Ramneek Singh
Satvinder Pal Singh


]]> 2018-11-21 20:39:07 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306846767 Group 1, by Liu Naiqian, Lin Sikai https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847202 2018-11-21 20:41:43 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847202 GROUP 3 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847617 Aditya Bhanu 300986549
Abhijit Singh 300983068
Amritpal Singh 300989163]]> 2018-11-21 20:44:28 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847617 Group 5 Jeremy Marshall 300948343, Swetha Manivannan 300983984, Mohamed Shajahan 300969224 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847670 2018-11-21 20:44:49 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847670 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847924 Harwinder singh 300984088
Ketan Kumar 300984684]]> 2018-11-21 20:45:46 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306847924 Arshdeep Kaur (300985883) ( Group 2) https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306848272 Yejin sim
Abdullah ]]> 2018-11-21 20:47:41 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306848272 Group 4 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306849015 Arshdeep singh 300965588
Gurwinder singh 300982016
Himanshu dang 300986169

]]> 2018-11-21 20:52:05 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306849015 Group 2 https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306849860 Arshdeep Kaur( 300985883)
Yejin Sim ( 300946577)
Abdullah Rahimi (300975351)

Question 2
 (b)
 We chose alternate hypothesis ]]> 2018-11-21 20:57:17 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306849860 group 1: Diallo, Oumar Bachir and Ngoc Duy Nguyen https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306850568 2018-11-21 21:01:54 UTC https://padlet.com/dstanescu63/jbuesm7i1jlq/wish/306850568