1. Explain why the formula for sample variance divides SS by n - 1 instead of dividing by n. 2. for the following data, find the range and the semi-interquartile range: 3,4,5,7,9,10,11,13

3. for the following population of N=6 scores: 8,6,2,6,3,5

a. sketch a histogram showing the population distribution.

b. Locate the value of the of the population mean in your sketch, and make an estimate of the standard deviation

c, compute SS, variance, and standard deviation for the population (How well does your estimate compare with the actual value of o?}

Image result for 1. Explain why the formula for sample variance divides SS by n - 1 instead of dividing by n.

The reason dividing by n-1 corrects the bias is because we are using the sample mean, instead of the population mean, to calculate the variance. ... In other words, using the sample mean to calculate the variance is too specific to the dataset.

solution:

we have to construct

∠m nt ≅ ∠p qr

the steps to draw this construction are

step 1: use a compass to draw an arc from point q which intersects the side pq at point a and the side qr at point b.

step 2: draw a segment nt and use the same width of the compass to draw an arc from point n which intersects the segment nt at a point x.

step 3:

step 4: join points n and y using a straightedge.

step 3:

option (d).maintaining the same width of the compass as ab, draw an arc from point x such that it intersects the arc drawn from n in a point y.

to draw   congruent angles , 1. width of compasses while drawing two angles should be same i.e from point at which angle has to be drawn, 2.the distance between the two points where the compass intersects the two sides should be same while drawing any two congruent angles.