Recent research into the cost of various medical procedures has shown the impact
ID: 3256496 • Letter: R
Question
Recent research into the cost of various medical procedures has shown the impact of certain complications encountered in surgery on the total cost of a patient’s stay in the hospital. The researchers used regression analysis and found the following results: Total cost for patient = Constant, plus a × Length of stay (measured in days), plus b × Presence of one or more complications (= 1 if true, 0 if false), plus c × Use of a laparoscope (= 1 if true, 0 if false) Where: • a, b, c are coefficients of the regression model, and • The laparoscope is an instrument somewhat like a miniature telescope with a fiber optic system which brings light into the abdomen. It is about as big around as a fountain pen and twice as long. The following table shows additional regression results presented by the researchers in the study described above. There are two regressions. The right-hand column shows the results for all patients, including those treated with laparoscopic surgery. The left-hand column shows the results for the sample of patients who were treated without the laparoscopic surgery, and the related costs.
Calculate the t-value for each of the independent variables. (Round your answers to 2 decimal places.) Blocks that need answered have answer required in the spreadsheet below
Nonlaparoscopic Patients Only All Patients Coefficients for Independent Variables t-value t-value Regression intercept $8,666 $3,455 Length of stay Coefficient Not significant 831 Standard error for the coefficient Not applicable 86 Answer Required Number of complications Coefficient 3,920 1,871 Standard error for the coefficient 1,070 Answer Required 557 Answer Required Laparascopic Coefficient Not applicable 974 Standard error for the coefficient Not applicable 341 Answer Required R-squared 0.26 0.51Explanation / Answer
Answer:
Nonlaparoscopic Patients Only
All Patients
Coefficients for Independent Variables
t-value
t-value
Regression intercept
$8,666
$3,455
Length of stay
Coefficient
Not significant
831
Standard error for the coefficient
Not applicable
86
9.66
Number of complications
Coefficient
3,920
1,871
Standard error for the coefficient
1,070
3.66
557
3.36
Laparascopic
Coefficient
Not applicable
974
Standard error for the coefficient
Not applicable
341
2.86
R-squared
0.26
0.51
tvalue=coefficient/standard error
831/86=9.66
3920/1070=3.66
1871/557=3.36
974/341=2.86
Nonlaparoscopic Patients Only
All Patients
Coefficients for Independent Variables
t-value
t-value
Regression intercept
$8,666
$3,455
Length of stay
Coefficient
Not significant
831
Standard error for the coefficient
Not applicable
86
9.66
Number of complications
Coefficient
3,920
1,871
Standard error for the coefficient
1,070
3.66
557
3.36
Laparascopic
Coefficient
Not applicable
974
Standard error for the coefficient
Not applicable
341
2.86
R-squared
0.26
0.51
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.