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Step by step solution

01

Step-by-Step SolutionStep 1: Estimating sample estimates

02

Least square prediction method

03

Step 3:Sum of square of residuals ,mean squared of error, and   S2

S2=SSEn-(k+1)=151,01620-(2+1)=151,01617

Interpretation: Value of s close to 0 indicates that the data is clustered around the mean. However, high value of s indicates that the data points are clustered above the mean value. Also, approximately 95% of the observations should fall between the range of +/- 2s

Therefore,s=8883.294=94.251

04

 Testing the significance of  β1

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Confidence interval for β2

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Step 6:  R2and adjusted   R2

The value of R2and adjusted is calculated using R2

07

Testing the overall significance of the model

Using the given hypothesis testing, overall significance of the model can be found as;

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 Overall significance of the model

To comment on the overall significance of the model, F statistic can be found like

The observed 5% significance level for the test conducted in part g would be

Fα,16,16=2.33

Since F test statistic > F observed value, reject the null hypothesis that β1=β2=0

Therefore, the data provides strong evidence that at least one of the coefficients in the model is a nonzero number.

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Most popular questions from this chapter

Forecasting movie revenues with Twitter. Refer to the IEEE International Conference on Web Intelligence and Intelligent Agent Technology (2010) study on using the volume of chatter on Twitter.com to forecast movie box office revenue, Exercise 11.27 (p. 657). Recall that opening weekend box office revenue data (in millions of dollars) were collected for a sample of 24 recent movies. In addition to each movie’s tweet rate, i.e., the average number of tweets referring to the movie per hour 1 week prior to the movie’s release, the researchers also computed the ratio of positive to negative tweets (called the PN-ratio).

a) Give the equation of a first-order model relating revenue (y)to both tweet rate(x1)and PN-ratio(x2).

b) Which b in the model, part a, represents the change in revenue(y)for every 1-tweet increase in the tweet rate(x1), holding PN-ratio(x2)constant?

c) Which b in the model, part a, represents the change in revenue (y)for every 1-unit increase in the PN-ratio(x2), holding tweet rate(x1)constant?

d) The following coefficients were reported:R2=0.945andRa2=0.940. Give a practical interpretation for bothR2andRa2.

e) Conduct a test of the null hypothesis, H0;β1=β2=0. Useα=0.05.

f) The researchers reported the p-values for testing,H0;β1=0andH0;β2=0 as both less than .0001. Interpret these results (use).

Write a model relating E(y) to one qualitative independent variable that is at four levels. Define all the terms in your model.

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a. Explain why the valueβ^0=325790has no practical interpretation.

b. Explain why the valueβ^1=-321.67should not be Interpreted as a slope.

c. Examine the value ofβ^2to determine the nature of the curvature (upward or downward) in the sample data.

d. The researchers used the model to estimate “that just after the year 2021 the fleet of cars with catalytic converters will completely disappear.” Comment on the danger of using the model to predict y in the year 2021. (Note: The model was fit to data collected between 1984 and 1999.)

Question: Consumer behavior while waiting in line. The Journal of Consumer Research (November 2003) published a study of consumer behavior while waiting in a queue. A sample of n = 148 college students was asked to imagine that they were waiting in line at a post office to mail a package and that the estimated waiting time is 10 minutes or less. After a 10-minute wait, students were asked about their level of negative feelings (annoyed, anxious) on a scale of 1 (strongly disagree) to 9 (strongly agree). Before answering, however, the students were informed about how many people were ahead of them and behind them in the line. The researchers used regression to relate negative feelings score (y) to number ahead in line (x1) and number behind in line (x2).

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d. From their analysis, the researchers concluded that “the greater the number of people ahead, the higher the negative feeling score” and “the greater the number of people behind, the lower the negative feeling score.” Use this information to determine the signs of β1 and β2 in the model.

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