Deneme Sınavı Soruları

Which sampling method provides observation of habits, opinions, and viewpoints in the easiest possible manner?

(Answer the questions 9 and 10 according to following information)

A sales manager assesses that %60 of their costumers are happy with their product. A sample of 150 customers were selected randomly and it was found that 80 of them are happy with the product. Test the sales manager assessment at %95 confidence level.

What is the test statistic at this hypothesis testing?

There are 40 observations in a population. A sample of 4 observations are to be selected randomly using a table of random numbers. Here are the the random numbers obtained from the table of random numbers: 55, 34, 67, 89, 12, 23, 89, 78, 18, 99, 92, 16, 45, and 10. In which random number given in this list, the process of selecting sample should be stopped?

Which of the following is true about t distribution?

If a sample proportion of a variable in an investigation is 42%, then what is the point estimate of the population proportion?

As the Central Limit Theorem states, What is the type of distribution of the independent samples approximates?

In a hypothesis testing procedure, the population mean and standard deviation are 800 and 200 respectively. On the other hand, sample arithmetic mean of a random sample of 225 observations is 950. If this procedure is followed, what is the value of the observed z?

In two population hypothesis testing which of the following is true?

Which of the following statements is false regarding the test statistic formula below, which is for two sample tests of means when their population variances are known?

A random sample of a data set is as follows: 3, 4, 4, 4, 7,4, 5, 6, 7, and 9. What is the point estimate of the population arithmetic mean?

If there are 120 objects in a population and the investigator wants to use simple random sampling to choose objects in to a sample from this population, what is the probability of a object to be selected in to a sample?

Which of the following is not necessary when calculation a confidence interval for an unknown population mean?

For sample one the sample size is 10, mean is 4.5, and standard deviation is 1. For sample two the sample size is 12, mean is 3.4, and standard deviation is 1.2 and (µ1 −µ2 ) is considered to be equal to 0. What is the test statistics for the given values? 

In a production line, the mean weight of the products should be 450 grams and the standard deviation of the weight variable is σ = 25. It is known that the distribution of the weights of the packages follow a normal distribution. A sample of 32 observations is randomly selected from the production line in the afternoon and the sample average is found as of 448 grams.The significance level α = 0.05 for this problem.

If you follow the five step hypothesis testing procedure, what is the alternative hypothesis for the situation given above ? 

In which statistical method, we might write down the following hypothesis:

"Is there any difference for the mean number of defective products which are manufactured by two different machine operators?"

What is the difference between stratified and cluster sampling?

In a classroom there are 25 students. Out of these 25 students 10 of them are male. If a hypothesis testing procedure for the population proportion of female students is to be created, what is the value of the sample proportion of the female students?

Interval estimation : the limits of the confidence interval are (0.41, 0.97), the significance level is 0.01. What is the sample arithmetic mean?

In which sampling methods one uses stratums?