Question

The null hypothesis is that the average high temperature in December is 45 degrees. If someone reports that the average was 52 degrees and that the P-value for this is 0.036, what does the P-value represent?

Answer 1

@ash2326 @ajprincess @bahrom7893 @electrokid

Answer 2

@ganeshie8 @hartnn

Answer 3

?

Answer 4

@reemii ?

Answer 5

The aim of hypothesis testing is to be able to say "there is this much chance (95% for example) that this (the null) hypothesis is liekly to be true".

In common terms, the p-value is the probability that something weirder than the null hypothesis will happen. If it is very small, that means that the null hypothesis is weird itself..

If the p-value is 0.036 (= 1 - 0.963), the null hypothesis is unlikely, but if you want to be sure, say, at 99%, you should not reject the possibility that the null hyothesis is wrong.

Answer 6

So iw ould put: If the p-value is 0.036 (= 1 - 0.963), the null hypothesis is unlikely, but if you want to be sure, say, at 99%, you should not reject the possibility that the null hyothesis is wrong.

Answer 7

thanks @reemii can u help with something else?

Answer 8

ok

Answer 9

Use the following information for the below questions:
The New Yorker, a local newspaper for Manhattan, New York conducted a poll on the 1996 governor's race. They took a random sample of 1200 voters in Manhattan and reported that 72% of those surveyed would vote for the Democratic candidate and announced that the margin of error was ±3% for 95% confidence in the survey results. At the same time, the Gallup organization also conducted a poll of 498 voters in Manhattan and reported that 68% of those surveyed would vote for the Democratic candidate and announced that the margin of error was ±4% for 95% confidence interval in the survey results.

Why does The New Yorker poll have a smaller margin of error than the Gallup poll in the information above?

Answer 10

The Gallup poll will have more bias present in the experiment
The Gallup poll is more honest because they are a nationally recognized organization

The New Yorker is the local paper, so it knows its own people better and will therefore be able to get more effective results

The Gallup organization is larger, therefore it will have a larger margin of error

The New Yorker took a larger sample size, so it will have a smaller margin of error

Answer 11

Is your question "Why does The New Yorker poll have a smaller margin of error than the Gallup poll in the information above?" ?

The third sentence: "The New Yorker took a larger sample size, so it will have a smaller margin of error" is correct.

For the technical detail about the ±3% and ±4%:
there is a factor \(\frac{1}{\sqrt{n}}\) involved in this margin, so the bigger \(n\) the smaller the margin.

Answer 12

okay cool r u sure about that one?

Answer 13

you mean, the third sentence?

Answer 14

Yeah. but there are 5 options total

Answer 15

The Gallup poll will have more bias present in the experiment

The Gallup poll is more honest because they are a nationally recognized organization

The New Yorker is the local paper, so it knows its own people better and will therefore be able to get more effective results

The Gallup organization is larger, therefore it will have a larger margin of error

The New Yorker took a larger sample size, so it will have a smaller margin of error

Answer 16

So, it is E? for sure?

Answer 17

B, C and D are not right because they mention irrelevent information or they suppose some people are more honest than others. No no: a poll is a poll
A) might be, (what exactly do they mean by bias?) but E) answers really more the question.
I would defintely choose E.

Answer 18

Ok thanks! ok i have another one, its simple just need your help plz @reemii

Answer 19

The following hypotheses are tested:

H0: µ= µ0 and HA: µ? µ0

Based on an SRS of size n form a normal population, We are said to commit a Type 2 error if we

Answer 20

Accept the alternative when the null is true

Reject the null when in fact the null is true

Reject the null when the alternative is true

Accept the null when the null is true

Accept the null when the alternative is true

Answer 21

i forgot, but wiki will tell me in a second.. done: Type2 error: we accept something that is false.
so last option.

Answer 22

so its accept the null when the alt is true? u 100 percent sure?

Answer 23

From wiki: A type II error, also known as an error of the second kind, occurs when the null hypothesis is false, but erroneously fails to be rejected.

It is the " Accept the null when the alternative is true" for sure, 100% ;-)

Answer 24

ok ya i agree too i just found! ok another one lol sorry but almost donenad your eing really helpful

Answer 25

A national interest rate on houses for 25 years is 4.3%. A banker in a large northwestern city believes that the local interest rates are lower than the national rate. What is the null hypothesis that this banker wishes to test?

Answer 26

Ho: mean equals 4.3 percent
Ho: mean doesnt equal 4.3 percent
Ho: mean less than 4.3 percent
Ho: mean greater than 4.3 percent
Ho: mean less than or equal to 4.3 percent

Answer 27

There are two options: "rate is 4.3%" and "the banker thinks it's smaller".
So, \(H_0\) and \(H_1\) are : rate=4.3, and rate<4.3. But which one is \(H_0\) ?

To choose, it's simple, we must choose the one that "fixes" a value (this enables computation of p-values ;) ). Therefore we choose to test \(H_0\):rate=4.3 versus \(H_1\):rate<4.3.

Answer 28

i think its A?

Answer 29

please PM (mail) me I need to go now..
gl

Answer 30

what is PM???

Answer 31

@reemii

Answer 32

@reemii ????

Answer 33

I would say, Ho: rate equals 4.3%.
Reason: the test will be [equals 4.3] VS [smaller than 4.3]. And we must choose something that has fixed the value of a parameter, otherwise calculations are not possible.
So: Ho: rate equals 4.3 percent.