Statistical Methods-Tests of Significance (ISS Statistics Paper I (Old Subjective Pattern)): Questions 1 - 4 of 17

Get 1 year subscription: Access detailed explanations (illustrated with images and videos) to 165 questions. Access all new questions we will add tracking exam-pattern and syllabus changes. View Sample Explanation or View Features.

Rs. 550.00 or

Question number: 1

» Statistical Methods » Tests of Significance » Chi-Square

Appeared in Year: 2013

Essay Question▾

Describe in Detail

From along series of annual river flows, the variance is found out to be 49 units. For a new sample of 25 years, the variance is calculated as 81 units. Can we regard that the sample variance is significant? (Given the chi-square value at 5 % level of significance as 37.7)

Explanation

The sample size is 25. Here we test

H0:σ2=σ02vsHA:σ2σ02

The null hypothesis is tested by chi-square test when the sample size is less than 30. The test statistic is

χ2… (113 more words) …

Question number: 2

» Statistical Methods » Tests of Significance » T-Test

Appeared in Year: 2014

Essay Question▾

Describe in Detail

Define power of a test and discuss its role in selecting the best test. Describe a test procedure for testing equality of means of two independent normal populations, when standard deviations are equal but unknown for small samples.

Explanation

Power of a test: The power function is the probability of rejection the null hypothesis when the alternative hypothesis is true. In statistical terms,

P(RejectH0H1)=1β

The quantity 1-β is called the power of the… (292 more words) …

Question number: 3

» Statistical Methods » Tests of Significance » Z-Test

Appeared in Year: 2009

Essay Question▾

Describe in Detail

A manufacturer of alkaline batteries expects that only 5 % of his products are defective. A random sample of 300 batteries contained 10 defectives. Can we conclude the proportion of defectives in the entire lot is less than 0.5 at 5 % level of significance?

Explanation

A random sample of 300 batteries contained 10 defectives. A manufacturer of alkaline batteries expects that only 5 % of his products are defective that is testing of hypothesis is

H 0: P = 0.05 against H 1: P < 0.05

Here n = 300, numbers of defectives… (139 more words) …

Question number: 4

» Statistical Methods » Tests of Significance » T-Test

Appeared in Year: 2010

Essay Question▾

Describe in Detail

You are working as a purchase manager for a company. The following information has been supplied to you by two manufacturers of electric bulbs.

Company A

Company B

Mean life

1300

1288

Standard deviation

82

93

Sample size

100

100

Which brand of bulbs are you going to purchase if you desire to take a risk of 5%?

Explanation

Here the sample size is n = 100

The standard deviation and mean of two samples is different. The null hypothesis is the mean life of bulb of company A is equal to the mean life of bulb of company B and alternative its differ.

H0:μ1… (195 more words) …

Sign In