# S3 help neededWatch

#1
i dont understand how they did part e
Why did they do P(M=0)= 27/125+ 54/125
and why did they do P(M=1)
i dont even understand the question as well what does the sampling distribution of mode M even mean.
0
#2
here is the question and worked example
0
1 year ago
#3
(Original post by assassinbunny123)
here is the question and worked example
A sampling distribution is a probability distribution of a statistic obtained through a large number of samples drawn from a specific population. The sampling distribution of a given population is the distribution of frequencies of a range of different outcomes that could possibly occur for a statistic of a population.

So, in this case - the mode is the statistic. Every sample from the population is different and therefore will give a different mode. All the different modes will form a range of modes that the population can take. The probability associated with each mode from each sample forms the probability distribution of the mode. This is known as the sampling distribution of the mode.

Clearly, there are two possibilities of numbers that the counters can have: 0 or 1.

A simple random sample of size 3 is taken from this population.

E.g. (0,1,1). It can also be (0,0,0), (1,1,1), (1,0,1) etc.
So, as you can see - different samples from the same population give a different mode.
(0,1,1) --> mode = 1.
(0,0,0) --> mode = 0, etc.

In part (b), you listed all the possible samples that can possibly be taken from the population.
Work out the modes for each one and the associated probability of getting that sample e.g. (0,0,0) = 0.6 * 0.6 * 0.6 = (0.6^3) because there is a probability of 0.6 of getting a 0.

The example does it very nice in part (c), they listed the cases next to the probabilities. It is clear that the first two lines, i.e. (0,0,0) case and the next line all have a mode of 0.

If you add the probabilities of those samples, you get 81/125.
The other possibility is a mode of 1. The probabilities always add up to 1. So P(M = 1) = 1 - (81/125).

On the other hand, you could use the last two lines of part (c) to find the probability of getting a mode of 1. Then, subtract this from 1 to find the probability of getting a mode of 0.
1
#4
If i ever meet you in real life i'll give you a hug. thank you very much for this valuable information
(Original post by Chittesh14)
A sampling distribution is a probability distribution of a statistic obtained through a large number of samples drawn from a specific population. The sampling distribution of a given population is the distribution of frequencies of a range of different outcomes that could possibly occur for a statistic of a population.

So, in this case - the mode is the statistic. Every sample from the population is different and therefore will give a different mode. All the different modes will form a range of modes that the population can take. The probability associated with each mode from each sample forms the probability distribution of the mode. This is known as the sampling distribution of the mode.

Clearly, there are two possibilities of numbers that the counters can have: 0 or 1.

A simple random sample of size 3 is taken from this population.

E.g. (0,1,1). It can also be (0,0,0), (1,1,1), (1,0,1) etc.
So, as you can see - different samples from the same population give a different mode.
(0,1,1) --> mode = 1.
(0,0,0) --> mode = 0, etc.

In part (b), you listed all the possible samples that can possibly be taken from the population.
Work out the modes for each one and the associated probability of getting that sample e.g. (0,0,0) = 0.6 * 0.6 * 0.6 = (0.6^3) because there is a probability of 0.6 of getting a 0.

The example does it very nice in part (c), they listed the cases next to the probabilities. It is clear that the first two lines, i.e. (0,0,0) case and the next line all have a mode of 0.

If you add the probabilities of those samples, you get 81/125.
The other possibility is a mode of 1. The probabilities always add up to 1. So P(M = 1) = 1 - (81/125).

On the other hand, you could use the last two lines of part (c) to find the probability of getting a mode of 1. Then, subtract this from 1 to find the probability of getting a mode of 0.
0
1 year ago
#5
(Original post by assassinbunny123)
If i ever meet you in real life i'll give you a hug. thank you very much for this valuable information
Lol no worries ❤️
0
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### University open days

• Regent's University London
Thu, 19 Sep '19
• Durham University
Fri, 20 Sep '19
• Loughborough University
Fri, 20 Sep '19

### Poll

Join the discussion

Rock (193)
24.13%
Pop (193)
24.13%
Jazz (31)
3.88%
Classical (46)
5.75%
Hip-Hop (153)
19.13%
Electronic (53)
6.63%
Indie (131)
16.38%