The following table shows the annual number of PhD graduates in a country in various fields. 1990 1995 2000 2005 2010 2012 Natural Sciences 70 130 330 490 590 690 Engineering 10 40 130 370 550 590 Social Sciences 50 100 280 450 830 1,000 Education 30 40 130 210 520 900 (a) Use technology to obtain the regression equation and the coefficient of correlation r for the number of social science doctorates as a function of time t in years since 1990. (Round coefficients to three significant digits. Round your r-value to three decimal places.) y(t) =

The following table shows the annual number of PhD graduates in a country in various fields. 1990 1995 2000 2005 2010 2012 Natural Sciences 70 130 330 490 590 690 Engineering 10 40 130 370 550 590 Social Sciences 50 100 280 450 830 1,000 Education 30 40 130 210 520 900 (a) Use technology to obtain the regression equation and the coefficient of correlation r for the number of social science doctorates as a function of time t in years since 1990. (Round coefficients to three significant digits. Round your r-value to three decimal places.) y(t) =

Algebra & Trigonometry with Analytic Geometry

13th Edition

ISBN:9781133382119

Author:Swokowski

Publisher:Swokowski

Chapter7: Analytic Trigonometry

Section7.6: The Inverse Trigonometric Functions

Problem 91E

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The following table shows the number, in millions, of women employed outside the home in the given year.Use regression to find a quadratic model for the data.
An investigation into the relationship between an adolescent mother's age x in years and the birth weight y of her baby in grams yielded the regression equation y= - 1163.45 + 245.15x as well as r = .88369, r2= .78091, SSE = 337212.45, and s= 205.30844 1) What is the predicted birth weight for a baby brn to a 17 year old woman? 2) What is the propotion of the variability in the weights of babies born to adolescent mothers that is accounted for by the mother's age? 3) For every additional year in the mother's age that mean birth weight of the baby? (a) increases by about 245g (b) decreases by about 245g (c) increases by about 1163g (d) increases by about 1163g (e) changes by an amount that cannot be determined from the information given.
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Assume that there is a positive linear correlation between the variable R (return rate in percent of financial investment) and the variable t (age in years of the investment) given by the regression equation R = 2.5t + 5.3. 1- If the investment continues to grow at a constant rate, what is the expected return rate when the investment is 7 years old?