54) option b)
Don't reject H0
55) option a)
In stepwise regression, we start with basic model, & keep on adding variable till it turns out to be significant, with lower p values
This test whether added variables are jointly & individually significant or not
Exercise 54 Consider the null hypothesis Ho:B2 = B3 = 0 against the alternative Hu: B26=...
16. The correlation coefficient p between two variables is -0.63 for a sample of 20 observations. The null hypothesis is Ho : p = 0. Which of the following is a correct conclusion based on the data given? Use the 0.05 significance level. A. Reject the null H. There is a negative association between the variables. B. Do not reject the null Ho. There is a negative association between the variables C. Reject the null Ho. There is a positive...
Question 4 (3 points) The statsmodels ols() method is used on a cars dataset to fit a multiple regression model using Quality as the response variable. Speed and Angle are used as predictor variables. The general form of this model is: Y = Bo + B. Speed+B Angle If the level of significance, alpha, is 0.10, based on the output shown, is Angle statistically significant in the multiple regression model shown above? Select one. OLS Regression Results ==================================== ========== 0.978...
Need help with stats true or false questions Decide (with short explanations) whether the following statements are true or false a) We consider the model y-Ao +A(z) +E. Let (-0.01, 1.5) be a 95% confidence interval for A In this case, a t-test with significance level 1% rejects the null hypothesis Ho : A-0 against a two sided alternative. b) Complicated models with a lot of parameters are better for prediction then simple models with just a few parameters c)...
Alejandra is using a one-sample ?‑test to test the null hypothesis ?0:?=10.0 against the alternative ?1:?<10.0 using a simple random sample of size ?=15. She requires her results to be statistically significant at level ?=0.05. Determine the maximum value of ?t that will reject this null hypothesis. You may find this table of ?t‑critical values useful. If you are using software, you may find this catalog of software guides useful. Give your answer to three decimal places. ?=
An aircraft company wanted to predict the number of worker-hours necessary to finish the design of a new plane. Relevant explanatory variables were thought to be the plane’s top speed, its weight, and the number of parts it had in common with other models built by the company. A sample of 27 of the company’s planes was taken, and the following model was estimated: y = b0 + b1x1 + b2x2 + b3x3 + e where y = design effort,...
Use the following linear regression equation to answer the questions. x1 = 1.5 + 3.4x2 – 8.3x3 + 2.3x4 (a) Which variable is the response variable? Which variables are the explanatory variables? (b) Which number is the constant term? List the coefficients with their corresponding explanatory variables. constant? x2 coefficient? x3 coefficient? x4 coefficient? (c) If x2 = 1, x3 = 8, and x4 = 6, what is the predicted value for x1? (Use 1 decimal place.) (d) Explain how...
Use the following linear regression equation to answer the questions. x1 = 1.7 + 3.9x2 - 8.1X3 + 1.9x4 (a) Which variable is the response variable? O O O O Which variables are the explanatory variables? (Select all that apply.) o X3 O X4 Сх, (b) Which number is the constant term? List the coefficients with their corresponding explanatory variables. constant X2 coefficient Xz coefficient x4 coefficient (C) If x2 = 8, X3 = 3, and X4 = 1, what...
I. IF we do not reject the null hypothesis when the alternative hnthsinthen we have made Type B error (b) Correct decision (e) Type I error (a) Type I1 error Use for Problems 2 and 3. The data below shows the top 10 teams' winning percentages (z) and powe ratings (u) for the 2013-2014 NCAA basketball season, according to vww.teasrankings.com bo 100.47 b 20.43 08330.694 2. Interpret the estimated slope of the line. (a) For a 1-game decrease in power...
Use the following linear regression equation to answer the questions. X1 = 1.7 + 3.6x2 - 8.4x3 + 1.5x4 (a) Which variable is the response variable? O X1 O X2 O X4 O X3 Which variables are the explanatory variables? (Select all that apply.) X3 X1 U X2 (b) Which number is the constant term? List the coefficients with their corresponding explanatory variables. constant X2 coefficient X3 coefficient X4 coefficient (c) If x2 = 8, X3 = 5, and x4...
Q7) A hypothesis test is to be performed with a Null hypothesis and an alternative hypothesis , the population standard deviation is σ=3.0, the sample size is 30, and the significance level is α=0.025. What is a type I error? (1 mark) What is the chance of making a type I error in the above test? (1 mark) What is a Type II error? (1 mark) What value would the sample mean have to be greater than to reject Ho? (2 marks) It is...