Applicants for a Particular Job,which Involves Extensive Travel in Spanish-Speaking

question 19

Multiple Choice

Applicants for a particular job,which involves extensive travel in Spanish-speaking countries,must take a proficiency test in Spanish.The sample data were obtained in a study of the relationship between the numbers of years applicants have studied Spanish and their score on the test.Use the regression analysis and summary statistics given below to find a 95% confidence interval for the average score of an applicant who has studied Spanish for 2.2 years. $$\begin{array} { l l l l c } \text { Variable } & \text { Count } & \text { Mean } & \text { StdDev } & \text { Range } \\\text { Years } & 10 & 3.5 & 0.341565 & 3 \\\text { Score } & 10 & 69.7 & 4.088058 & 41\end{array}$$ Dependent variable is: Score R-squared = 83.0%
S = 5.65138 with 10 - 2 = 8 degrees of freedom $$\begin{array} { l l l l l } \text { Variable } & \text { Coefficient } & \text { SE(Coeff) } & \text { t-ratio } & \text { P-value } \\\text { Constant } & 31.53333 & 6.360418 & 4.957745 & 0.00111 \\\text { Number of years } & 10.90476 & 1.744054 & 6.252538 & 0.000245\end{array}$$

• A)51.5 to 59.5
• B)43.1 to 70.9
• C)43.7 to 67.3
• D)48.9 to 62.2
• E)40.9 to 70.2

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Definitions:

Type I Error

The incorrect rejection of a true null hypothesis, also known as a false positive.

Level Shift

A sudden and lasting change in the average value of a time series or signal.

Level Shift

A sudden, lasting change in the time series data that can significantly affect the data's trend, usually detected through statistical analysis.

Cycle

In the context of data analysis, a period or sequence of events that repeats regularly.