Statıstıcs Iı Çıkmış Sorular, Online Deneme Sınavları, Çalışma, Dersler, Sınava Hazırlanma, vize, final

Soru 1:

________________________ includes similar distribution of important characteristics (e.g., age, gender, marital status, health status) with the distributions of those characteristics in the population?

A) A bad B) A representative sample C) A database D) An average E) Standard deviation

Soru 2:

if the type I error is 0.05 and a two-sided hypothesis testin is investigated, what is the z value from the standard normal distribution table?

A) 1.96 B) 2.18 C) 1.65 D) 2.33 E) 1.88

Soru 3:

what is the last step of hypothesis testing?

A) Select a level of significance B) Formulate a decision rule C) Identify the test statistic D) Take a sample and make the decision E) State null and alternate hypotheses

Soru 4:

"In ..... sampling method, the members, who are identified previously, are asked to identify other members of the population. As newly identified members name others, the sample is getting larger." Which of the following completes the blank in given sentence?

A) Cluster B) Systematic C) Simple random D) Stratified E) Snowball

Soru 5:

I. Rejecting the null hypothesis in an ANOVA test means at least one of the means of the population under consideration is different from the other population means. II. To compare two means through hypothesis testing procedure which is called one-way analysis of variance (one-way ANOVA) technique used to compare the means of two populations. III. Rejecting the alternative hypothesis in an ANOVA test means at least one of the means of the population under consideration is different from the other population means. Which of the given statements about ANOVA test can said to be true?

A) Only I B) Only II C) I and II D) I and III E) II and III

Soru 6:

In which sampling methods the sample includes the individiuals which are ready and availiable?

A) Quota sampling B) Snowball sampling C) Convenience sampling D) Cluster sampling E) Systematic sampling

Soru 7:

A researcher wants to compute the mean weight of a certain product produced by a firm. The firm produces 8000 products per day and each product has a serial number from 1 to 8000. The researcher decide to choose 80 products in order to compute average weight. He chooses the products with serial numbers 3, 103, 203,303, 403, 503......7903. Which method of sampling did the researcher apllied?

A) Systematic sampling B) Cluster sampling C) Stratified sampling D) Sampling with replacement E) Convenience sampling

Soru 8:

Sample values for a continuous variable (electric voltage at home ; as volt) : 204, 214, 226, 234, and 242. What is the point estimate of the population arithmetic mean?

A) 220 B) 222 C) 224 D) 226 E) 228

Soru 9:

In Eskisehir, 10 students were selected randomly from each of 3 universities to participate in a survey. Which type of sampling method was used?

A) systematic B) multi stage C) cluster D) stratified E) simple random

Soru 10:

Which test statistic do we use when the population variances are unkonwn and the sample size is smaller than 30?

A) z-test B) x-test C) t-test D) y-test E) Chi-test

Soru 11:

Which of the following is true about t distribution ?

A) The total area under a t-curve is 1 or 100%. B) The t distribution is unsymmetrical. C) The mean of the t distribution is all equal to one. D) The median and mode of the t distribution is equal to one. E) As the degrees of freedom decreases, the shape of the t distribution approaches to the standard normal distribution.

Soru 12:

The observed z value is 3.62 and theoretical z value is 1.96, then what is the conclusion for hypothesis testing?

A) Fail to reject null hypothesis B) accept null hypothesis C) accept the alternate hypothesis D) Fail to accept the alternate hypothesis E) cant conclude

Soru 13:

Population of university A is 20.000, population of engineering students is 5.000 (25 % take statistics course), population of psychology students is 400 (25 % take statistics course), population of statistics students is 400. How many people are there in the target population for a survey about statistics courses?

A) 5.800 B) 5.400 C) 1.750 D) 1.350 E) 400

Soru 14:

Which one of the following is a nonprobability sampling method?

A) Simple random sampling B) Stratified sampling C) Snowball sampling D) Cluster sampling E) Systematic sampling

Soru 15:

If you reject the null hypothesis when the null hypothesis is false, what is the decision?

A) Type I error B) Type II error C) 1- ß D) ß E) Correct decision

Soru 16:

For the means of two normal distributions, what is the null hypothesis for two sided (two tailed) test?

A) H0 : µ1 – µ2 = 0 B) H0 : µ1 < µ2 C) H0 : µ1 – µ2 = 1 D) H0 : µ1 > µ2 E) H0 : p1 = p2

Soru 17:

where can we write down the following hypothesis "Is there any difference for the mean number of defective products which are manufactured by two different machine operators?"

A) ANOVA B) One sample hypothesis testing C) Regression analysis D) Hypothesis testing for two populations E) Kolmogorov-Smirnov

Soru 18:

A researcher wants to decide whether the average Statistics 101 course exam scores of students of faculty of engineering and faculty of natural sciences are same or not. He takes 60 students from faculty of engineering whose average exam score is 59, and 50 students from faculty of natural sciences whose average score is 65. The variance regarding the exam scores for engineering faculty is 15, and that for natural sciences faculty is 10. What will be the z-statistics for this comparison?

A) 8.94 B) 7.62 C) 6.45 D) 5.63 E) 4.86

Soru 19:

Sample values for a continuous variable (noise level of a laptop computer ; as decibel) : 16, 19, 23, 24, 27, 32, 17, and 10. What is the point estimate of the population arithmetic mean?

A) 18.0 B) 19.0 C) 20.0 D) 21.0 E) 22.5

Soru 20:

For a statistical test following a normal distribution, the alternative hypothesis is that the mean equals to a hundred and the standard deviation is s = 20. A sample of 25 observations is randomly selected and the sample average is equal to 102. What is the test statistic equal to?

A) 0.35 B) 0.40 C) 0.45 D) 0.5 E) 0.55