All Exams Test series for 1 year @ ₹349 only
Question

The data given in the table are fitted to the equation $y = mx$ using the method of least squares. The value of $m$ is ______ (rounded off to one decimal place).
$x$1234
$y$26710

Least Squares Fitting

The problem requires fitting the given data to the linear equation $y = mx$ using the method of least squares to find the value of the slope, $m$.

Data Table Analysis

The provided data points $(x_i, y_i)$ are:

$x$ $y$
1 2
2 6
3 7
4 10

Summation Calculations

To apply the least squares method for the equation $y = mx$, we need the following sums:

  • Sum of $x$ values: $\sum x_i = 1 + 2 + 3 + 4 = 10$
  • Sum of $x^2$ values: $\sum x_i^2 = 1^2 + 2^2 + 3^2 + 4^2 = 1 + 4 + 9 + 16 = 30$
  • Sum of $x \cdot y$ values: $\sum x_i y_i = (1 \times 2) + (2 \times 6) + (3 \times 7) + (4 \times 10) = 2 + 12 + 21 + 40 = 75$

Slope Calculation Formula

The formula for the slope $m$ in the least squares fit for $y = mx$ is:

$m = \frac{\sum x_i y_i}{\sum x_i^2}$

Calculating Slope 'm'

Substitute the calculated sums into the formula:

$m = \frac{75}{30}$ $m = 2.5$

Final Result Presentation

The calculated value of $m$ is $2.5$. The question asks for the value rounded off to one decimal place. The value $2.5$ is already precise to one decimal place.

Therefore, the value of $m$ is 2.5.

Was this answer helpful?

Important Questions from Regression Analysis

  1. If a constant 60 is subtracted from each of the values of X and Y, then the regression coefficient is

  2. Given the regression lines X + 2Y - 5 = 0, 2X + 3Y - 8 = 0 and Var(X) = 12, the value of Var(Y) is

  3. The standard deviation of Y is double of standard deviation of x. The correlation coefficient between X and Y is 0.5.

    The acute angle between lines of regression is

  4. For the variables X, Y and Z, r xy = 0.80, r xz = 0.64, and r yz = 0.79, the square of multiple correlation coefficient \(\rm \mathop R\nolimits_{xyz}^2 \)  is:

  5. Dimension reduction methods have the goal of using the correlation structure among the predictor variables to accomplish which of the following:

    A. To reduce the number of predictor components

    B. To help ensure that these components are dependent

    C. To provide a framework for interpretability of the results

    D. To help ensure that these components are independent

    E. To increase the number of predictor components

    Choose the correct answer from the options given below:

Need Expert Advice?

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App