AS Biology - Student's t-test and Spearman's rank (OCR A Chapter 10.6)

***Just spotted a mistake in my notes!***
For the "left hand side" of the critical value diagram, when t-value or Spearman's rank coefficient is LOWER than critical value at p=0.05, it should say:
"Therefore less than 95% confidence that there is significant difference or there is a correlation"
NOT "more than 95% confidence" which is the same as the one on the right...
I USED THE WRONG ARROW ON THE LEFT!!
So: my handwritten one is wrong, but my verbal explanation and the typed out example is CORRECT!
Sorry! :(

There are a few possible types of questions in exams on stats:
- Pick a statistical test to prove a certain point (so you'll need to know the purpose of each test)
- Calculate the actual value (use the equation given and be careful)
- Interpret the value in comparison to the critical value given in probability table
- Formulate a good conclusion.
The calculations aren't that bad if you're careful, so here we'll be focusing on how to interpret and structure a good conclusion to get the marks.

Please subscribe for more content and comment below to let me know what you think! :)

Facebook: BioRach - A-level Biology Online

Twitter: @BioRachProject

Background music:

[BioRach]

***Just spotted a mistake in my notes!***
For the "left hand side" of the critical value diagram, when t-value or Spearman's rank coefficient is LOWER than critical value at p=0.05, it should say:
"Therefore < 95% confidence that there is significant difference or there is a correlation"
NOT "> 95% confidence" which is the same as the one on the right...
I USED THE WRONG ARROW ON THE LEFT!!
So: my handwritten one is wrong, but my verbal explanation and the typed out example is CORRECT!
Sorry! :(

[ishs]

Oh my goodness thank you so much!!, we had the most terrible biology teacher in year 12 that completely missed the biodiversity topic as well as others but you’re videos are really helping me to catch up ready for my exams🙏🙏

[lycheemango]

Please keep making these videos! They are the most amazing revision resources and really help some of the trickier topics the books tend to overcomplicate! We have plant hormones coming up soon and it's great to see you are still making these videos! Keep up the good work! :)

[slinkyneko]

This was super helpful! I wish my teachers could have explained it as well as you did. Thanks!

[Crackheads]

You are really great. I just love your explanation ♥️

[malanhemal]

Hi Biorach,
What's the difference between an unpaired and paired t test?

[michelleokueguale]

Hi biorach i recently found your videos and I have to say they are really good and clear and straight to the point. Would you be able to make videos on the cardiac cycle Bohr shift transport of oxygen. Could you make a video dedicated to biodiversity in the new ocr a biology please thank you 😊

[kiransandhu]

Hi Miss, I'm just going through these videos, and they are so helpful and to the point! Thanks for covering the content in an easy and understandable way! My teacher was right for recommending you!

As I'm going through, I've noticed there isn't a 10.5 video? I was just wondering if you have a video for this part of the topic?

[danyah]

i'm confused... how do you calculate the degrees of freedom for Spearman's rank?

[justin-nxjz]

is this the same for chi squared? as my teacher said its flipped but I think he is wrong

[apatchy]

Is the critical value always 5%? I have no idea where to start with this - teaching myself in lockdown

[kiransandhu]

will we ever have to work out the critical value?

[piasytric]

On the smaller side, did you mean to write <95% instead?? Because you wrote them the same on both sides

[adamgrecula]

Hello Biorach,
Amazing video but i would just like to ask, our biology teacher taught us that we aren't allowed to say that 'we accept the null hypothesis', but rather we should say 'we are unable to reject the null hypothesis'. I also study psychology and choosing statistical tests is also a common exam question and came up in 2/3 papers this year. I was taught for psychology that we say that 'we accept the null hypothesis'.
I was wondering whether there is a significant difference (excuse the pun 😂) between these ways of saying that the null hypothesis is correct.

Thank you for saving my biology exams!

[malanhemal]

Hi Biorach, I love your videos, but sometimes the things you say are cut. So, what you say is not fully heard. I thought it might helpful for me and other students who watch your videos.

Love your videos, thank you !

Have a Great Day!

[ZestyGecko]

do we need to memorise the equations of Rs and t or is it given?

[munaaliii]

Can we have your email, miss. and Thank you so much you explain so clearly and calmly, very helpful. <)