On a TI-84... 1. Hit STAT 2. Go to TESTS on the far right hand side. 3. Go down to "5: 1-PropZTest" 4. Plug in all the numbers. (Po is the null hypothesis, n is the sample total, x is the amount given within the sample.) 5. Be wary of the PROP section. (not equal to, less than, or greater than) 6. You're welcome.
I've spent.. 6 hours trying to find a formula, or something, to figure this out. I get that I should've applied myself more during class, maybe attending tutoring, BUT THANK YOU!!!
+Rachel Welke As I state in the description, "I assume that you know how to find areas under the standard normal curve." Continually going back and showing people how to find those areas is a complete waste of time for those that are up to speed. I have videos showing how to find areas under the standard normal curve, for those that need to catch up.
+Rachel Welke Finding Areas Using the Standard Normal Table (for tables that give the area to left of z) (6:16) (ruclips.net/video/-UljIcq_rfc/видео.html) Finding Areas Using the Standard Normal Table (for tables that give the area between 0 and z) (8:55) (ruclips.net/video/dwRVY0FjpQM/видео.html)
If you are assuming Z is normally distributed, then these tests are wrong surely? It should be two sided as Z can achieve values less than AND greater than mu_0.
It is found from the standard normal distribution, using either software or a standard normal table. At this point in a typical statistics course, students have long since encountered the standard normal distribution, and are able to find these areas. If you need to learn how to find these areas, I have videos illustrating how to do so. I also have an annotation link at the appropriate point of this video, saying "Don't know how to find this area? Click here to watch me find it using a table."
Doesn't the formula for the Z score not include the square root of the sample? From my 2 minutes of research its the (observed value - mean of the sample)/Standard Deviation of the sample. There is no Square root of the number of samples in the formula.
As I say in the description: " I assume that you know how to find areas under the standard normal curve." If you don't know how to find areas under the standard normal curve, then that's something to learn before trying to learn the material in this video.
P-values are based on the observed data, and not the significance level. We compare a p-value to the significance level, but the p-value calculation does not depend on the significance level.
I have always learnt that if there is a < sign in Ha (H1) then it is a left tailed test and if there is > sign the a right failed test. I am feeling a little confused. I also want to thank you for the videos and the reply. God bless.
How did you get 0.0764 for the Z score of 1.43? This is the value for -1.43. I hope I am not confused. If you check the Statistics table for -1.43, you will get 0.076, but here we have a right tailed test hence + 1.43. SO we check the positive table for Z score which gives us 0.9082 value for + 1.43. Please help me understand this. Thank you for all your effort.
ajazbashirable In that example we needed to find the area to the right of 1.43 under the standard normal curve. Your table most likely gives the area to the left of the z value you look up, which would be 0.9236 in this case. The area to the right is 1 minus this value. Your area of 0.9082 is the area to the left of 1.33, not 1.43.
ajazbashirable The value 0.73 is greater than 0, and is therefore found on the right side of the standard normal distribution. In this example, the alternative hypothesis is that mu is less than the hypothesized mean, so the p-value is the area to the left of 0.73. But 0.73 falls where it falls, and that does not change between the different alternative hypotheses.
okay but how do i find the pvalue
is the probability of Z (Area)
P(Z>1.43)=0.076358509536739
On a TI-84...
1. Hit STAT
2. Go to TESTS on the far right hand side.
3. Go down to "5: 1-PropZTest"
4. Plug in all the numbers. (Po is the null hypothesis, n is the sample total, x is the amount given within the sample.)
5. Be wary of the PROP section. (not equal to, less than, or greater than)
6. You're welcome.
junowhatt God bless your ducking soul. You’re a LIFE SAVER
I love you
Didnt work. H0 or P0 was 170. Sample mean is 175 and n is 36. All it gave me was an error saying Domain
I've spent.. 6 hours trying to find a formula, or something, to figure this out.
I get that I should've applied myself more during class, maybe attending tutoring, BUT THANK YOU!!!
Not helpful for actually how to find P-value at all. lol.
+Rachel Welke As I state in the description, "I assume that you know how to find areas under the standard normal curve." Continually going back and showing people how to find those areas is a complete waste of time for those that are up to speed. I have videos showing how to find areas under the standard normal curve, for those that need to catch up.
+jbstatistics could you link to those? I obviously couldn't find them.
+Rachel Welke Finding Areas Using the Standard Normal Table (for tables that give the area to
left of z) (6:16) (ruclips.net/video/-UljIcq_rfc/видео.html)
Finding Areas Using the Standard Normal Table (for tables that give the area
between 0 and z) (8:55) (ruclips.net/video/dwRVY0FjpQM/видео.html)
If you are assuming Z is normally distributed, then these tests are wrong surely? It should be two sided as Z can achieve values less than AND greater than mu_0.
Taking the first case, you need H0
This is the simplest and most precise explanation i have ever found on RUclips. JB, you are the best!! Thank you.
You are very welcome!
On the first example, I found. 0764 on the negative side of the z-scores. Shouldnt the score be ..9236 if it's a right tail test?
It is found from the standard normal distribution, using either software or a standard normal table. At this point in a typical statistics course, students have long since encountered the standard normal distribution, and are able to find these areas. If you need to learn how to find these areas, I have videos illustrating how to do so. I also have an annotation link at the appropriate point of this video, saying "Don't know how to find this area? Click here to watch me find it using a table."
Incredibly amazing how well you explain things!
Doesn't the formula for the Z score not include the square root of the sample? From my 2 minutes of research its the (observed value - mean of the sample)/Standard Deviation of the sample. There is no Square root of the number of samples in the formula.
For last one where did the area come from? You have to be more detailed
As I say in the description: " I assume that you know how to find areas under the standard normal curve." If you don't know how to find areas under the standard normal curve, then that's something to learn before trying to learn the material in this video.
But then why the p-values differ based on the significance level?
P-values are based on the observed data, and not the significance level. We compare a p-value to the significance level, but the p-value calculation does not depend on the significance level.
Watch this video only if you already know how to calculate area from z table.
Thanks. You saved my ass!
is there a way you can find the p-value without looking at the table ?
This is really helpful, you explained it way better than my prof! Thank you so much
I have always learnt that if there is a < sign in Ha (H1) then it is a left tailed test and if there is > sign the a right failed test. I am feeling a little confused. I also want to thank you for the videos and the reply. God bless.
How did you get 0.0764 for the Z score of 1.43? This is the value for -1.43. I hope I am not confused. If you check the Statistics table for -1.43, you will get 0.076, but here we have a right tailed test hence + 1.43. SO we check the positive table for Z score which gives us 0.9082 value for + 1.43. Please help me understand this. Thank you for all your effort.
ajazbashirable In that example we needed to find the area to the right of 1.43 under the standard normal curve. Your table most likely gives the area to the left of the z value you look up, which would be 0.9236 in this case. The area to the right is 1 minus this value. Your area of 0.9082 is the area to the left of 1.33, not 1.43.
Shouldn't Z=0.73 be on the left side. If Ha has < sign then it is left tailed test. Right?
ajazbashirable The value 0.73 is greater than 0, and is therefore found on the right side of the standard normal distribution. In this example, the alternative hypothesis is that mu is less than the hypothesized mean, so the p-value is the area to the left of 0.73. But 0.73 falls where it falls, and that does not change between the different alternative hypotheses.
Not helpful at all.
I need p value of left tailed, right tailed, two tailed if z value is 1.75 ho is rejected at alpha value 5%
You not showing HOW using the tables
I have separate videos on how to use the tables.
wtf do you mean so how do we find the p value -_-
quite helpful - not sure why others are not able to find the p-value after watching this video.
THANKS SO MUCH OMG LIFE SAVER. I WAS GOING MENTAL TILL I WATCHED YOUR VIDEO. HOPE I ACE STATS. U R AWESOME!!!!111!!!!11!!
why don't you how to find p-value
Thank you - found my answer from this video.
Very Useful Sharing and Nice Teaching always.
Awesome explanation. Thank you.
this explains what it is in context to the z test, but not how to use the z test number to get the p-value. fail.
I got the P- Value for the 1.43 as .9263
Subtract it from 1.
I actually understand.
Thank you so much!
Very informative thank
thank you!! so helpful
super helpful! thanks
You are very welcome Gregory!
Great Vid, thanks !
You are very welcome Evan.
This was perfect thank you so much ;n;
You are very welcome!
Amazing!
THANK YOU!!!!
talks way too fast
+jack periccos Those preferring a slower approach may wish to watch an updated version of this video at ruclips.net/video/m6sGjWz2CPg/видео.html.
I cant understand still.. Poor explanation.... Indeed.. I can read the book instead of this video...