Seçmeli Ara Sınav - Statıstıcs Iı

Soru 1:

I. There are four possible correct and incorrect decision-making situations that may occur through statistical hypothesis testing. II. Type I error is defined as failing to reject the null hypothesis (H 0 ) when it is actually false. III. Type II error is defined as rejecting the null hypothesis (H 0 ) when it is actually true. Which of the given statements about incorrect decisions through hypothesis testing can be said to be true?

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

Soru 2:

Population can be finite or ___________ ?

A) Parameter B) Infinite C) Restricted to 500 D) Smaller than 1250 E) Bigger than 100

Soru 3:

I. Random numbers can be used to select simple random samples from a population frame. II. Each possible sample combination of the specified size does not have equal probability of being chosen. III. It is the most basic sampling method. Which of the given is TRUE about simple random sampling?

A) Only I B) I & II C) I & III D) II & III E) I, II & III

Soru 4:

What is the critical z-value for ? =0.05?

A) 1.75 B) 1.96 C) 2.11 D) 2.20 E) 2.33

Soru 5:

A random sample of 410 from two class in a high school is chosen. 250 of the students is selected from class (A) and their particular subject's mean test score is 70 with a standard deviation of 5. The rest of the students is selected from class (B) and their mean test score is 65 with a standard deviation of 4. At the 1% significance level, can we conclude that class (A) mean test score is better than the class (B)?

A) 20 B) 25 C) 30 D) 35 E) 40

Soru 6:

The weight variable is ? = 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. What should be alternate hyphothesis in this situation?

A) The mean weight of the packages is less than 448 grams. B) The mean weight of the packages is less than 450 grams C) The mean weight of the packages is equal to 448 grams. D) The mean weight of the packages is equal to 450 grams. E) The mean weight of the packages is more than 448 grams.

Soru 7:

The titles of term projects for psychology course were written separetely on pieces of papers then placed in a black box. Then, student A selected 2 papers from the box. Which type of sampling methods was used in this sampling ?

A) stratified B) snow ball C) systematic D) simple random E) cluster

Soru 8:

___________________ is the universe to be sampled, such as all Turkish people, all universities in Turkey, all pregnant women over 40 years of age, all adult males who smoke 20 cigarettes or more daily, or all the buildings in Eskişehir, Turkey?

A) Sample B) Parameter C) Statistics D) Population E) Database

Soru 9:

I. Choose the level of significance ?. II. Determine the population proportion under study and form the null hypothesis (H0 ) and the alternative hypothesis (H1 ). III. Identify the critical points and critical region for the hypothesis test. IV. Calculate the test statistic z for proportions. V. Based on sample information decide to reject or fail to reject the null hypothesis (H0 ) and interpret the results of the hypothesis test. What is correct order of the steps of hypothesis testing given above?

A) I- II - IV - III - V B) II - I - IV - III- V C) II- I - IV - V -III D) II- I - III- IV - V E) IV -II- I - III- V

Soru 10:

For Group 1 and Group 2 data that are normally distributed, and the population variances are not equal, we can we conclude that there is a the mean of Group 1 is greater than the mean of Group 2. What is the alternative hypothesis?

A) H1: µ1≠ µ2 B) H0: µ1≠ µ2 C) H1: µ1< µ2 D) H0: µ1> µ2 E) H1: µ1> µ2

Soru 11:

Which of the following is true about the population?

A) Populations are always homogenous. B) Populations are always finite. C) The size of the population is smaller than the sample. D) Populations always contain more than 1000 items. E) Populations can contain any type of objects.

Soru 12:

In which situation below, can hypothesis tests for proportions be used?

A) Mid-term results of students who have a score above fifty B) Quality engineers test the proportion of parts that are defective or not defective C) The workers who are older than 50 years old D) The engineers who use the new management software E) The teacher who take online professional development courses

Soru 13:

In which sampling methods one uses stratums?

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

Soru 14:

A researcher wants to test whether the average exam scores of two students groups (X and Y respectively) are same or not. How will he formulate null hypothesis (H0) and alternative hypothesis (H 1 )?

A) H0: XY B) H0: YX C) H0: X=Y, H1: X D) H0: X=Y, H1: X>Y E) H0: X=Y, H1: X≠Y

Soru 15:

A hypothesis test which is a _________________ that uses sample statistics to test a claim or assumption about the value of a population parameter?

A) data collection process B) decision-making process C) sampling process D) data cleaning process E) averaging process

Soru 16:

what is the total size of the rejection region in hypothesis testing?

A) 1– β B) H0: μ = μ0 C) H1: μ ≠ μ0 D) 1- α E) α

Soru 17:

For the variance between samples equalling 10 and the variance within samples equaling 50, what is the test statistic for a one-way ANOVA test is the ratio of two variances?

A) 0.1 B) 0.2 C) 0.3 D) 0.5 E) 1.5

Soru 18:

In a problem, the variance between samples is 200 and the test stastic F is 2. What is the variance within samples?

A) 10 B) 20 C) 60 D) 100 E) 202

Soru 19:

In which of the following sampling methods subgroups occur naturally (such as departments of a company)?

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

Soru 20:

Population of country A is 500.000, population of males is 240.000 (25 % are students), population of females is 260.000 (30 % are students). How many people are there in the target population for a survey to determine sports habits of students?

A) 260.000 B) 240.000 C) 138.000 D) 78.000 E) 60.000