## Hypothesis Testing - Single population Variances

muthuthere
Posts: 7
Joined: Tue Sep 29, 2015 8:47 am

### Hypothesis Testing - Single population Variances

Hi,
As per slides in quants three if
Ho: Pop Variance >= sample Variance
Ha: Pop Variance < sample Variance
So it is single tailed and tail is lower tailed

Question in page 9 (quants 3).. By Video May 2015

Ho: Pop Variance >= sample Variance
Ha: Pop Variance < sample Variance
But they considered that as upper tail.

If we take upper tail and lower tail wrongly the whole decision will change. Can u pl. explain which is correct?

edupristine
Finance Junkie
Posts: 947
Joined: Wed Apr 09, 2014 6:28 am

### Re: Hypothesis Testing - Single population Variances

Hi,
Can you please mention the exact question in which you are facing problem?

muthuthere
Posts: 7
Joined: Tue Sep 29, 2015 8:47 am

### Re: Hypothesis Testing - Single population Variances

A brand new air conditioner from Carrier must maintain the selected temperature with little variation. Specifications from the company call for a standard deviation of not more than 2 degrees (or variance of 4 degrees2). A sample of 4 air conditioners is tested and yields a sample variance of s2= 6. Test to see whether the standard deviation specification is exceeded.Use = 0.05