Mathematics, 17.03.2020 04:09 maxraph108

A group of researchers conducted a study to determine whether the final grade in an honors section of introductory psychology was related to a student’s performance on a test of math ability administered for college entrance. The researchers looked at the test scores of 200 students (n= 200) and found a correlation of r= .45 between math ability scores and final course grade. The proportion of the variability seen in final grade performance that can be predicted by math ability scores is .

Answers: 3

Show answers

Answers

Answer from: zayzay162

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

And for this case r =0.45

The % of variation is given by the determination coefficient given by r^2 and on this case 0.45^2 =0.2025 , so then the % of variation explained is 20.25%.

The proportion of the variability seen in final grade performance that can be predicted by math ability scores is 20.25%.

Step-by-step explanation:

For this case we asume that we fit a linear model:

y = mx+b

Where y represent the final grade and x the math ability scores

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

$\bar x= \frac{\sum x_i}{n}$

$\bar y= \frac{\sum y_i}{n}$

And we can find the intercept using this:

$b=\bar y -m \bar x$

The correlation coeffcient is given by:

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

And for this case r =0.45

The % of variation is given by the determination coefficient given by r^2 and on this case 0.45^2 =0.2025 , so then the % of variation explained is 20.25%.

The proportion of the variability seen in final grade performance that can be predicted by math ability scores is 20.25%.

Answer from: Quest

11/2.2 = 5 inches for the length 8.5/2.2= 3.86 inches for the width

Answer from: Quest

"it's not the heat, it's the humidity". that's a partly valid phrase you may have heard in the summer, but it's actually both. the heat index, also known as the apparent temperature, is what the temperature feels like to the human body when relative humidity is combined with the air temperature. this has important considerations for the human body's comfort. when the body gets too hot, it begins to perspire or sweat to cool itself off. if the perspiration is not able to evaporate, the body cannot regulate its temperature. evaporation is a cooling process. when perspiration is evaporated off the body, it effectively reduces the body's temperature. when the atmospheric moisture content (i.e. relative humidity) is high, the rate of perspiration from the body decreases. in other words, the human body feels warmer in humid conditions. the opposite is true when the relative humidity decreases because the rate of perspiration increases. the body actually feels cooler in arid conditions. there is direct relationship between the air temperature and relative humidity and the heat index, meaning as the air temperature and relative humidity increase (decrease), the heat index increases (decreases).

step-by-step explanation:

75% of the temperatures are below what value? how do you know? 75% of the temperatures are above w

Another question on Mathematics

Mathematics, 21.06.2019 14:00

Question 1(multiple choice worth 1 points)(07.06 mc)a group of students must collect at least $150 to organize a science fair. they have already collected $30. which graph best represents all remaining amounts of money, in dollars, that thestudents should still collect to organize the science fair? -210 -180 -150 - 120 -90-60 -300306090 120 150 180 210-210 -180 -150 - 120 -90 -60 -30 0 30 60 90 120 150 180 210-210 -180-150 - 120 -90-60-300 30 60 90 120 150 180 210-210 -180 -150 - 120.90 -60 -30 0 30 60 90 120 150 180 210

Answers: 3

Answer

Mathematics, 21.06.2019 17:30

Miranda is braiding her hair.then she will attach beads to the braid.she wants 1_3 of the beads to be red.if the greatest number of beads that will fit on the braid is 12,what other fractions could represent the part of the beads that are red?

Answers: 3

Answer

Mathematics, 21.06.2019 21:30

A(1,1) b(-3,0) c(-4,-1) d(3,-2) drag it to correct position

Answers: 2

Answer

Mathematics, 21.06.2019 21:30

Using pert, adam munson was able to determine that the expected project completion time for the construction of a pleasure yacht is 21 months, and the project variance is 4. a) what is the probability that the project will be completed in 17 months? b) what is the probability that the project will be completed in 20 months? c) what is the probability that the project will be completed in 23 months? d) what is the probability that the project will be completed in 25 months? e) what is the due date that yields a 95% chance of completion?

Answers: 3

Answer

You know the right answer?

A group of researchers conducted a study to determine whether the final grade in an honors section o...

Questions