Tutors Answer Your Questions about Correlation (FREE)
Question 1170317: An architect wants to determine the relationship between the heights (in feet) of a building and the number of stories in the building. The data for a sample of 10 buildings are shown below. Explain the relationship.
Stories 64 54 40 31 45 38 42 41 37 40
Height 841 725 635 616 615 582 535 520 511 485
Click here to see answer by CPhill(2138)   |
Question 1170330: An architect wants to determine the relationship between the heights (in feet) of a building and the number of stories in the building. The data for a sample of 10 buildings are shown below. Explain the relationship.
Stories 64 54 40 31 45 38 42 41 37 40
Height 841 725 635 616 615 582 535 520 511 485
Click here to see answer by josgarithmetic(39702) |
Question 1181445: On the basis of the following information of x and y series consisting of 15 pairs of observations calculate of correlation coefficient :
x -series : X = 25 ूx 3.01
y -series : Y = 18 ूy3.03
Summation of products of corresponding deviation of x and y series = 122.
Click here to see answer by CPhill(2138) |
Question 1187210: Q No.6)
Part a)
The following table shows verbal reasoning test score, x, and an English test score, y, for each of a random sample of 8 children who took both tests.
Child A B C D E F G H
x 112 113 110 113 112 114 109 113
y 69 65 75 70 70 75 68 76
Calculate the Co-efficient of correlation “r” between the scores in verbal reasoning and English.
Part b)
The age (X) and systolic blood pressure (Y) of 100 individuals gave the following sums:
X i 4421, Yi 12130, X i2 208349, Yi2 1498976, X iYi 542735
Determine the equation of the least squares regression line of Y on X.
the missing letter is sumation (E)
Click here to see answer by CPhill(2138) |
Question 1187211: The nine items of a sample had the following values:
45, 47, 50, 52, 46, 40, 49, 55, 66
Does the mean of the nine items differ significantly from an assumed normal population mean of 45 i.e., 45 at 0.05?
Click here to see answer by Boreal(15235)  |
Question 1170562: Each box of one brand of breakfast cereal contains a coupon entitling purchasers to a free package of vegetable seeds. At the home office, they use the weight of the incoming mail to determine the number of employees to be assigned to collecting coupons and sending out seed packages each day. (The company policy is that all mail received will be answered the same day.) Following is the data for a random sample of 8 days:
Weight of mail (pounds) 11 20 16 6 12 18 23 25
Number of employees 6 10 9 5 8 14 13 16
(a) Draw a scatter diagram for the data-discuss its shape (5 marks)
(b) Using Excel conduct the following regression models for the data
I. LineaR
II. Quadratic
III. Third degree polynomial
IV. Exponential
V. Logarithmic
VI. Power
(c) Determine which model is the best-state the reason for your belief. (5 marks)
(d) What percentage of the variation in the number of employees is explained by the regression model chosen.
(e) If the company receives 15 pounds of mail, how many employees should be assigned mail duty?
Click here to see answer by math_tutor2020(3828) |
Question 1114067: How strong is the correlation between the inflation rate and 30-year treasury yields? The following data published by Fuji Securities are given as pairs of inflation rates and treasury yields for selected years over a 35-year period.
Inflation rate (%) 30-year treasury yield (%)
1.57 3.05
2.23 3.93
2.17 4.68
4.53 6.57
7.25 8.27
9.25 12.01
5.00 10.27
4.62 8.45
Compute the Pearson productmoment correlation coefficient to determine the strength of the correlation between these two variables. Comment on the strength and direction of the correlation.
Keep 2 decimal places.
r =
There is a strong
relationship between the inflation rate and the thirty-year treasury yield.
Click here to see answer by Theo(13342)  |
Question 1011927: please help me solve this question
The vertices of a triangle are (1,a)(2,b)(c square,-3):-
(1) Prove that its centroid cannot lie on the Y - axis.
(2) Find the condition that the centroid may lie on the X - axis
Click here to see answer by KMST(5330)  |
Question 975289: With the aim of predicting the selling price of a house in Newburg Park, Florida, from the distance between the house and the beach, we might examine a regression equation relating the two variables. In the table below, the distance from the beach (x, in miles) and selling price (y, in thousands of dollars) for each of a sample of sixteen homes sold in Newburg Park in the past year are given. The least-squares regression equation relating the two variables is yhat=296.54-4.73x. The line having this equation is plotted in Figure 1.
====================
Figure 1
Distance from the beach, x (in miles):
6.8
7.4
14.2
3.8
6.5
11.7
12.1
10.9
9.6
10.6
14.6
8.4
17.8
4.6
13.1
5.5
Selling price, y 9 (in thousands of dollars):
240.0
217.6
188.0
259.0
303.0
222.9
281.7
284.4
233.8
197.6
265.9
296.2
226.0
313.1
200.9
268.4
====================
Based on the above information, answer the following:
(1) For these data, house prices that are greater than the mean of the house prices tend to be paired with distances from the beach that are [greater than or less than?] the mean of the distances from the beach.
(2) According to the regression equation, for an increase of one mile in distance from the beach, there is a corresponding decrease of how many thousand dollars in house price?
(3) What was the observed house price (in thousands of dollars) when the distance (in miles) from the beach was 17.8 miles?
(4) From the regression equation, what is the predicted house price (in thousands of dollars) when the distance (in miles) from the beach is 17.8 miles?
Click here to see answer by Fombitz(32388)  |
Question 936580: _________Researchers studying growth patterns of children collect data on the heights of fathers and sons. The correlation between the fathers heights and the heights of their 16 year old sons is most likely to be ...
A) Near Zero
B) Near +0.7
C) Somewhat greater than 1.0
D) Exactly +1.0
E) Near -1.0
Click here to see answer by ewatrrr(24785)  |
Question 934821: _________The correlation coefficient between high school grade point average (gpa) and college gpa is 0.560. For a student with a high school gpa that is 2.5 standard deviations above the mean, we would expect that student to have a college gpa that is _______________________the mean .
A) 2.5 SD above
B)0.56 SD above
C)equal to
D) 1.4 SD above
Click here to see answer by MathLover1(20854)  |
Question 934822: ____The correlation coefficient between the hours that a peron is awake during a 24-hour period and the hours that same person is asleep during a 24-hour period is most likely to be
A)Near 0 ; B)Near -0.8 ; C)Near +0.8 ; D)Exactly -1.0 ; E)Exactly +1.0
Click here to see answer by MathLover1(20854) |
Question 934822: ____The correlation coefficient between the hours that a peron is awake during a 24-hour period and the hours that same person is asleep during a 24-hour period is most likely to be
A)Near 0 ; B)Near -0.8 ; C)Near +0.8 ; D)Exactly -1.0 ; E)Exactly +1.0
Click here to see answer by jim_thompson5910(35256) |
Question 934824: _____The correlation coefficient between high school grade point average (gpa) and college gpa is 0.560. For a student with a high school gpa that is 2.5 standard deviations above the mean, we would expect that student to have a college gpa that is ________________________ the mean.
A)2.5 SD above
B)0.56 SD above
C)Equal to
D)1.4 SD above
Click here to see answer by MathLover1(20854) |
Question 934824: _____The correlation coefficient between high school grade point average (gpa) and college gpa is 0.560. For a student with a high school gpa that is 2.5 standard deviations above the mean, we would expect that student to have a college gpa that is ________________________ the mean.
A)2.5 SD above
B)0.56 SD above
C)Equal to
D)1.4 SD above
Click here to see answer by jim_thompson5910(35256) |
Question 934146: An investigation of a sample of 64 BBA students indicate that the mean time spent on preparing for examination was 48 months and the standard deviation was 15 months. What is the 95% confidence interval time spent by all BBA student before the complete their examination
Click here to see answer by ewatrrr(24785) |
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