Statıstıcs I Final 7. Deneme Sınavı

Toplam 20 Soru
PAYLAŞ:

1.Soru

The frequency distribution table of the students’ performance scores of a school were constructed as follows. What is the sample standard deviation of the data?


19,4

21,3

25,6

27,9

30,2


2.Soru

Data : 4, 4, 5, 5, 5, 15, 15, 18, 19, 15, 4, 5, 14, 14, 17, 17, 26, 26, 22, 22. What is the range of these data ?


4

5

14

26

22


3.Soru

Whish is TRUE about the table below specifying types of books a particular customer prefers?

                                      


It has the properties of classifying, magnitude, and equal intervals.

It has a natural or zero-valued base value that cannot be changed.

It is important that there is no any particular order or ranking for classes.

The consecutive categories do not represent equal differences of the measured attribute.

It is considered a nominal scale of measurement.


4.Soru

In how many d­ifferent ways can the letters i­n T H A N K S be arranged?


700

720

740

760

780


5.Soru

What is the variance of the probability distribution given above?


3.62

3.20

3

2.24

1.68


6.Soru

Suppose that random variable X has exponential distribution with ?=a. Find the probability of P (X ? b) ?


e-a/b

e-b/a

-e-b/a

e-ab

-e-ab


7.Soru

When the occurrence or non-occurrence of an event A does not affect the occurrence of another event B, then we say that A and B are statistically ........ events?


irrelevant

codependent

independent

dependent

random


8.Soru

Which of the followings is not true about normal distribution?


Normal distribution is one of the most significant and extensively used continuous probability distribution.

Normal distribution provides basis for the statistical inference.

Normal distribution was developed by a mathematician Karl Friedrich Gauss.

Normal distribution is an asymmetric distribution where the random variable values are uniformly scattered around the mean.

Normal distribution can be called as “bell curve” or  “Gaussian curve”.


9.Soru

Which of the statements below is correct?

I In classical probability, all the outcomes have the same chance of happening.

II In empirical probability, the experiments are repeated many times and the observed outcomes of the event we are interested in is counted.

III When it is not possible to observe the outcomes of events, the researcher applies the researcher assigns a suitable value as the probability of the event.

IV It is not appropriate to use personal judgement to assign the probability.


I and II

II and III

II, III and IV

I, II and III

II, III and IV


10.Soru

I. For any event A?S, P(A)?0. 

II. For any event A, P(A) = 1 – P (A)

III. For any two events A and B, P(A,B) = P(A) + P(B)

Which of the probability axioms can be said to be true?


Only I

Only II

I and II

I and III

II and III


11.Soru

Which probability approach uses the relative frequencies to assign the probabilities to the events?


Classical probability

Objective probability

Subjective probability

Positive probability

Empirical probability


12.Soru

A researcher wants to investigate the effects of tea on heart diseases. What should the researcher do in order to conclude a causal effect?


Ask a sample if they have a heart disease and how much tea they drink a day

Ask the patients with heart problems whether they are drinking tea

Give tea to a sample and observe what they are doing

Conduct an experiment with control and treatment groups

Survey a sample about their beliefs on the effect of tea on heart diseases


13.Soru

We know that event B has occurred and we are interested in finding the probability of event A. In other words, we are interested in finding the probability of A knowing that event B has occurred. Which of the following formula denotes the probability? We know that event B has occurred and we are interested in finding the probability of event A. In other words, we are interested in finding the probability of A knowing that event B has occurred. Which of the following formula denotes the probability?


P(A∩B) = P(A⏐B)P(B)

P(A∩B) = P(A⏐B)P(A)

P(A∩B) = P(A⏐B)

P(A∩B) P(A)= P(A⏐B)

P(A∩B) = P(A⏐B)P(B)P(A)


14.Soru

I. The time a person spends on reading a day

II. The amount of water a person drinks a day

III. The weight gain of a person in a month

Which of the variables given above are examples of a continuous random variable?


Only I

Only II

I and II

II and III

I,II and III


15.Soru

The observations are as follows; [14,15,15,16,17,18,20,21,20]

Which of the following is the Pearson’s coefficient of skewness (PCS) value of the data set above?


0,38

3,8

0,40

4

0,36


16.Soru

I. The air pressure on a tire on an automobile II.The number of students who actually register for classes  III. The amount of liquid in a can of cola IV. The temperature of a cup of coffee  Which of the variables above are examples of a continuous random variable?


I and II

I, II and III

I and III

I, II ve IV

I, III and IV


17.Soru

What is the set for the possible values of the random variable stated below?

"The number of coins that match when three coins are tossed at once."


{1,2}

{2,3}

{0,1}

{0,1,2}

{1, 2, 3}


18.Soru

The measures of ________ are another kind of descriptive statistics and give information about the shape of distribution of the observations.

Which option completes the blank in the description above?


Skewness

Variance

Standard Deviation

Interquartile Range

Box Plot


19.Soru

A s­ix-si­ded fai­r dic­e has been thrown 3000 times and the occurrence of number 4 ­is 450. What i­s the empirical probability of obtaining a number 4 when you throw a s­ix-si­ded fai­r dic­e?


0,15

0,20

0,25

0,30

0,35


20.Soru

Which information below is correct?

I The mean of a continuous random variable X is a weighted
average through the possible values of the random variable and associated probabilities.

II The mean of the continuous random variable is denoted by E (x).

III The mean is also called as expected value and denoted by µ. 

IV The variance is denoted by V(x) or ?2.


I, II

I,III

I, IV 

II,III

II, IV