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Chapter 5: Q6 (page 221)

In a USA Todaypoll, subjects were asked if passwords should be replaced with biometric security, such as fingerprints. The results from that poll have been used to create the accompanying table. Does this table describe a probability distribution? Why or why not?

Response

P(x)

Yes

0.53

No

0.17

Not Sure

0.3

Short Answer

Expert verified

The table does not describe a probability distribution as x is not a numerical variable.

Step by step solution

01

Given information

The data for the responses of the people who were asked if passwords should be replaced with biometric security is provided.

02

Step 2: Check whether the table describes a probability distribution

The requirements for a probability distribution table are as follows.

1)The variable x is a numerical random variable.In the given scenario, the variable is not numerical but categorical.

2)The sum of the probabilities is computed as

∑Px=0.53+0.17+0.3=1

Therefore,the sum of the probabilities is equal to 1.

3) Each value of the probability P(x) is between 0 and 1.

Here, the requirement of the variable to be numerical is not satisfied.

Therefore, the table does not describe a probability distribution.

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Most popular questions from this chapter

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