Essay errors Typographical and spelling errors can be either nonword errors or word

Chapter 6, Problem 51

(choose chapter or problem)

Get Unlimited Answers
QUESTION:

Typographical and spelling errors can be either “nonword errors” or “word errors.” A nonword error is not a real word, as when “the” is typed as “teh.” A word error is a real word, but not the right word, as when “lose” is typed as “loose.” When students are asked to write a 250-word essay (without spell-checking), the number of nonword errors X in a randomly selected essay has the following probability distribution:

\(\begin{array}{lccccc} \hline \text { Value: } & 0 & 1 & 2 & 3 & 4 \\ \text { Probability: } & 0.1 & 0.2 & 0.3 & 0.3 & 0.1 \\ \hline \end{array}\)

\(\mu_X=2.1\quad\ \ \ \ \ \sigma_X=1.136\)

The number of word errors Y has this probability distribution:

\(\begin{array}{lcccc} \hline \text { Value: } & 0 & 1 & 2 & 3 \\ \text { Probability: } & 0.4 & 0.3 & 0.2 & 0.1 \\ \hline \end{array}\)

\(\mu_Y=1.0\quad\ \ \ \ \ \sigma_Y=1.0\)

Assume that X and Y are independent.

An English professor deducts 3 points from a student’s essay score for each nonword error and 2 points for each word error. Find the mean and standard deviation of the total score deductions for a randomly selected essay. Show your work.

Questions & Answers


(1 Reviews)

QUESTION:

Typographical and spelling errors can be either “nonword errors” or “word errors.” A nonword error is not a real word, as when “the” is typed as “teh.” A word error is a real word, but not the right word, as when “lose” is typed as “loose.” When students are asked to write a 250-word essay (without spell-checking), the number of nonword errors X in a randomly selected essay has the following probability distribution:

\(\begin{array}{lccccc} \hline \text { Value: } & 0 & 1 & 2 & 3 & 4 \\ \text { Probability: } & 0.1 & 0.2 & 0.3 & 0.3 & 0.1 \\ \hline \end{array}\)

\(\mu_X=2.1\quad\ \ \ \ \ \sigma_X=1.136\)

The number of word errors Y has this probability distribution:

\(\begin{array}{lcccc} \hline \text { Value: } & 0 & 1 & 2 & 3 \\ \text { Probability: } & 0.4 & 0.3 & 0.2 & 0.1 \\ \hline \end{array}\)

\(\mu_Y=1.0\quad\ \ \ \ \ \sigma_Y=1.0\)

Assume that X and Y are independent.

An English professor deducts 3 points from a student’s essay score for each nonword error and 2 points for each word error. Find the mean and standard deviation of the total score deductions for a randomly selected essay. Show your work.

ANSWER:

Step 1 of 3

Given,

X = the number of nonword errors in a randomly selected essay.

The mean no. of nonword errors, \(\mu_{X}=2.1\)

The standard deviation of no. of nonword errors, \(\sigma_{X}=1.136\)

Y = The number of word errors in a randomly selected essay.

The mean no. of word errors, \(\mu_{Y}=1.0\)

The standard deviation of no. of word errors, \(\sigma_{Y}=1.0\)

Let’s find the mean and standard deviation of the total score deductions for a randomly selected essay:

Add to cart

Reviews

Review this written solution for 1055675) viewed: 1672 isbn: 9781464108730 | The Practice Of Statistics - 5 Edition - Chapter 6.2 - Problem 51

Thank you for your recent purchase on StudySoup. We invite you to provide a review below, and help us create a better product.

Textbook: The Practice of Statistics

Click to rate

Write a review below (optional):

Submit Review
×

Thanks for your review!

Think of all the students you've helped. Nice job!


Study Tools You Might Need

Not The Solution You Need? Search for Your Answer Here:

×

Login

Login or Sign up for access to all of our study tools and educational content!

Forgot password?
Register Now

×

Register

Sign up for access to all content on our site!

Or login if you already have an account

×

Reset password

If you have an active account we’ll send you an e-mail for password recovery

Or login if you have your password back