One small caveat: in broader mathematics, "number of bacterial colonies" would be treated as a *discrete variable*, which means the variable is numeric but it's restricted to certain values (and between those allowable values are gaps that the variable can't take on). But if you're plugging that variable into a regression or t-test/ANOVA model, then you're treating it as continuous. To quote minitab, which has great articles on statistics: "If you have a discrete variable and you want to include it in a Regression or ANOVA model, you can decide whether to treat it as a continuous predictor (covariate) or categorical predictor (factor). If the discrete variable has many levels, then it may be best to treat it as a continuous variable. Treating a predictor as a continuous variable implies that a simple linear or polynomial function can adequately describe the relationship between the response and the predictor. When you treat a predictor as a categorical variable, a distinct response value is fit to each level of the variable without regard to the order of the predictor levels. Use this information, in addition to the purpose of your analysis to decide what is best for your situation." support.minitab.com/en-us/minitab-express/1/help-and-how-to/modeling-statistics/regression/supporting-topics/basics/what-are-categorical-discrete-and-continuous-variables/

@madipsychomadi3144

4 жыл бұрын

thank you very much for your generous response.

@felixokatch4587

4 жыл бұрын

Good

@danielm9463

3 жыл бұрын

​@Raggul Kanakasabapathy, it sounds like it could go either way. I'm not an expert by any means, but I think you would decide whether to treat the independent variable as categorical vs continuous by asking questions like "do I expect a linear relationship between the input and output, such that more of the independent variable consistently leads to more/less of the dependent variable?" I think you can also ask questions like "for the purposes of my study, do I care about the *relationship* that the independent variable has to the dependent variable, or do I care about finding e.g. a single dose that is therapeutically significant?" Do you have reasons to expect that salt has a linear relationship (positive or negative) with plant growth? Are you interested in the specific nature of that linear relationship (e.g., is your goal is to say "for every 1 g of salt, the leaves grow X cm longer")? If so, then it might make more sense to treat mass as continuous. Alternatively, are you looking for whether a particular mass of salt exists which provides a statistically significant growth effect? Are there reasons why too little salt could inhibit growth, and too much salt could inhibit growth, but maybe there's a salt mass in the middle that could balance multiple biological factors and yield the most growth? If so, then it might make more sense to treat mass as categorical. The fact that you described 0 g of salt as the "control group" already suggests to me that you might be looking to compare salt vs. no salt, and the reason you have different amounts of salt is to help answer the question "do plants grow more effectively with salt than without salt?" In other words, having a control group suggests that you're not looking for the specific nature of a hypothesized linear relationship between amount of salt and amount of growth. I've never taught IB Bio, but I did teach IB Physics. If you're writing an IB Biology IA, I would think it's worthwhile to explain how you're analyzing your data and justify why you chose to treat the independent variable as categorical vs. continuous. If you choose to treat mass as categorical, then you've got a categorical independent variable and a continuous dependent variable--what test would you use in that circumstance? If you treat mass as numerical, then both the IV and DV are continuous--what test would you use in that circumstance? (By the way, you can still do a regression with a categorical independent variable, but that's not really done in IB Biology, and it sounds like this might not make sense in your case. Here's what it would entail. For each dose, you'd essentially have a different dummy variable that takes on a value of 0 or 1. So the variable m_1g would be 0 or 1, and the coefficient would tell you how much more/less growth the plant had compared to 0 g when 1 g of salt was added. The variable m_2g would similarly take on values of either 0 or 1, etc.) Another quick thing--if you go the route of performing multiple t tests (to compare each salt mass to the control group), then you want to watch out for family-wise error. You can do a quick Google search to see what this is. This is usually dealt with by lowering the p value that you need in order to reject the null hypothesis. For example, if you do 5 t-tests, and you'd normally use p < 0.05 as your significance level, then you might instead calculate 0.05/5 and use p < 0.01 as the significance level for each test, since performing multiple tests increases the likelihood of a false positive. There are different ways to account for this family-wise error, and the appropriate approach depends on the class you're in and how rigorous the statistics element is.

@danielm9463

3 жыл бұрын

@Raggul Kanakasabapathy Since it's an IA, I can't quite give you a direct answer--that will be up to you. All I'll say is that it sounds like you're saying you have a continuous IV, a continuous DV, and you seek the mathematical relationship. if you go the route of regression, I have a few thoughts: (a) I think regression and mathematical relationships are less common in IB Bio IAs. Because of that, I recommend asking your teacher if you're on the right track and if you have a suitable topic, question, and statistical analysis approach. (b) If you go the route of regression, I think you will want to be careful about how you phrase your research question. If your understanding is that regression is appropriate when seeking a mathematical relationship between a continuous IV and a continuous DV, then you want to phrase your research question as seeking that *mathematical* relationship between the variables. (c) In all of it, the ultimate goal is to use the analysis as a mechanism to talk about in-depth Biology analysis. So if you find a negative linear relationship, then you want to use the Biology you've learned to try and explain, in depth, *why* that relationship exists. (d) Since I've never taught IB Bio, definitely have a conversation with your teacher about all of this. The advice I'm giving you is good for IB Physics, but I'm not sure how much of it translates over to Biology.

@danielm9463

2 жыл бұрын

@Raggul Kanakasabapathy Hi Raggul, I was curious how your IA turned out! Were you happy with the final product?

Finally, the sky is clear....

This is perhaps the most simpliest and yet full tutorial I've heard on statistical tests LOL.....Well put together Daniel. Thanks

@danielm9463

3 жыл бұрын

Thanks for the kind message! I'm glad it was helpful

@mariabelenvargassanmartin2314

2 жыл бұрын

FACTS

This is by far the best material about SPSS I've ever seen in my whole life. Throw 100$ SPSS books into trash can. This video is very beautiful in a minimalist way. Greetings from a procrastinator doctor, who is trying to hurry analysis at 07:00 AM for the finish date of a paper :-)

9:57 minute video vs 6 weeks of lectures...just wow!

I have all this data I’ve collected for my masters thesis, I’ve been looking for a test to use for two days. This video, hands down, has just saved my life. THANK YOU!!!

@jaleelhull941

Жыл бұрын

how did it go

An amazingly simple description of statistical tests. Thank you so much!

After struggling for years trying to figure out about the necessity of so many statistical tests, finally I have an overview of statistical tools an how to choose one from.

Thank you so much for this video! Simple, concise, well organised -- it's rare to see such a well-made tutorial to a somewhat confusing topic such as this, amazing :)

Wow! I cannot express how much I am grateful to you for making this video. I spent one week figuring out which suitable statistical test was for my case. THANK YOU

Im from the Linguistics field in this is still helpful for my thesis, thank you!

I watched so many videos on this topic. But this is the best explanation so far. Thank you so much

Man, this guy nailed it. I fumbled in my undergrad research. I wish this was available to me then. Thank you, Sir.

Thanks for making it super simple, clear, and easy to understand!

I fell in love with the way you explained both the qualitative and quantitative techniques.

@danielm9463

2 жыл бұрын

Thanks Venu!

Thank you for this video. You did a great job of explaining the various statistical tests and their applicability.

For a broad perspective, this is a remarkable video. Nice work! This helps a lot

@danielm9463

4 жыл бұрын

Thanks so much, Don!

This video includes more data and has better educational content than what I learned in my MSc. Thank you Daniel.

Thanks to Allah.. I have found someone who is teaching the basics..I needed it badly

@asmasultana2732

3 жыл бұрын

Hello. I need some help from you

@mmmm7656

3 жыл бұрын

@@asmasultana2732 yes

@danielm9463

2 жыл бұрын

I'm glad it helped! I often need the basics too. This is a good starting place, but this video really does make some simplifications, and as you study more, you'll see that things aren't always so clear cut. I'm glad it helped!

Thanks man. Best explanation I've seen so far 👍

Very succinct and well put together. Thank you, Daniel!

Thank you sooo much for this video! It saved my life!I spent so many days trying to understand which test I should use for my master's thesis. You explained VERY well and simple! Thank you again.

This video has helped me more than my biology teacher, love you man

@danielm9463

2 жыл бұрын

Glad it helped! I sympathize with IB Bio teachers! They're expected to teach statistics, but it's not part of the curriculum!

I watched many videos on Hypothesis tests and always left with some sort of confusion. But you made it really simple. 🔥

From the bottom of my heart THANK YOU for this

After struggling for years trying to figure out about the necessity of Sr many statistical tests, finally I have an overview of statistical tools an how to choose one from.

Statistics are so simple and easy to understand after your wonderful explanation. Thank you for this amazing video.

@chaqsakhatanachaqsakhatana2325

Жыл бұрын

Stat is not easy subject 😭😒

Thanks for enlighten me on how to choose these statistical tests. I will be grateful to learn more.

half semester of my statistics class didnt give such comprehension, thank you for this well put video.

The Simplest and Most Comprehensive Demonstration of Tests...Thank You

Beautifully explained and simplified...... keep going 👍🏾

I like how the simplicity of your content, keep it up.

Thank you! Was recommended for Business Data Analytics. 4:08 is particularly useful if you're wondering what sort of test to use (or, what it's called!) Chi-Squared / t-Test / Correlation.

simply perfect and clear explanation . Thanks for your great effort

Best video I watched in statistics especially in experimental designs Thank you very much for that simple and valuable information

The most simpliest and useful tutorial i ever heard and seen. Thank you soo much for giving us such a wonderful lessons. 😊😊😊

Great job! It helped a lot in explaining the basics! Nice work!

Very brief and to the point. Great for a reasonable first overview of these topics. Thanks

I'm in IB Sports Exercise and Health Science but this video helped a lot for choosing the test for my IA. Thanks!

Simply the best and clearest explanation video.

This video is so well made! Thank you for your effort. It's really helping us out.

@danielm9463

2 жыл бұрын

Very glad to hear that! Check out the caveats I pinned at the top of the comments. Feel free to ask questions!

Simple, easy and best and proper way to have quick notes

Thorugh and simple to understand. Thanks

This video perfectly cleared everything up, thank you so much.

I don't know how you did it but you have helped me to know this better.

Awesome video! Thank you so much, Professor! Cheers from Brazil!

So helpful. Thank you! The basics make it easy to understand everything

Bravo! It is just the thing I needed to refresh my background after a long break

This helped me a lot, and I'm taking a graduate level class. Thank you!

Wow this simplified everything so much, thank you

The way to generalize test in a table is amazing!! Thanks! It really really helps a lot!

@danielm9463

2 жыл бұрын

Glad it helped! Just don't miss the correction I mentioned in the description

This video basically summarized two semesters of my statistics subject ngl.

Great video, I understood the concept clearly.. thanks alot!

Beautifully explained Daniel. Thank you

Sir you just nailed this video, you made me so damn clear about correlation. Thanks alot for your precious video😍

I wish you taught me Econometrics. Thank you for this.

Omg... I am a year 5 dental student and this vdo finally opened my mind...

Reaffirmed what I am beginning to grasp. Thank you!

I am not clear about which technique is used for the which study before observing this video. Now I clear about it . Thank you sir

Thanks for the explanation. 👍 Appreciate your efforts.

Comprehensive and over simplified.A great video.

thank you!! i need to use this info in my bio enzyme productivity analysis thesis!

tysm!! i would've had a breakdown if not for your video 🤧 also, the dun dun dun at 0:08 made me laugh so thanks for that too

Haters will say this clip is way too simple, I will respond yes that’s why it’s almost perfect.

Thank u so much! Very helpful for newbies like me ^^

your english is impeccable. i can clearly hear the proper pronunciation and enunciation. Concept is well explained.

@danielm9463

2 жыл бұрын

It's funny--I think people think I'm smarter than I am because I enunciate well :)

Very clear explanation. Thank you so much.

@danielm9463

2 жыл бұрын

Glad it helped!

One of the best explanations. Thanks much.

Thanks a lot for making me understand a lot better. Thank you once again.

Thank you so much, this is really helpful. I am even able to understand my own research thoroughly without thinking what was the reason why is it not relationship based.

Absolutely wonderful...!!!

Thanks Daniel! This helped a lot!!

best ever discussion in truly simple way. love from Bangladesh🇧🇩🇧🇩🇧🇩

This is so helpful, thank you!

This helps me a lot. Im going to use this on my report

Thank you very much for the simplest explanation

Thank you❤️. You've really helped me a lot.

Thank u sir u made it so simple to understand excellent presentation with explaination. Thank u too much

I'm slow when it comes to math (like "if johnny has 5 apples" type slow) and this breakdown finally made things clear

@danielm9463

28 күн бұрын

Don't hesitate to post any questions you have about your work or what you're studying!

Best ever teaching technique....

Best video on statistical tests

this helped me a lot, thank you

Amazing video

Very well explained! Thank you~

As simple as it can be...Thank you so much

currently doing my BIO IA. thank you

Crystal clear explanation!

@danielm9463

2 жыл бұрын

Thank you!

This was very helpful.thank u so much❤️

Dude this is really helpful. Thanks

Nicely explained. Best wishes from India

Iam from india , teaching research to post graduate students of education department.feel very helpful to understand overall category /families of statistics test.very excellent content of video 👍👍👍👍

Thanks for the vid, this greatly helped me with my math IA😂👍

Sooo good I literally cried

Very useful and clearly put information. Thanks

Correlation can be used on categorical data too! Not just continuous data.

@jincymathewm362

3 жыл бұрын

Yes, spearmans rank correlation

@mrkhan.881

2 жыл бұрын

Yes. But the dependent variable should always be continuous variable. And if the independent variable is Nominal then use Phi coefficient test and if ordinal then use Spearman.

@danielm9463

2 жыл бұрын

@@mrkhan.881 That's true for linear regression. Other regressions (e.g., logistic regression) do permit the dependent variable to be categorical.

@danielm9463

Жыл бұрын

@Tessa Owens, it's a good point. Really, a lot of the dichotomies in this intro video disappear in higher-level stats. You can reproduce the same p-values in Anova as a regression model, and you can set up dummy/indicator variables to encode categorical variables. The main audience for this video is high schoolers who haven't learned any stats but are expected to use it in their IB Biology IA.

@danielm9463

Жыл бұрын

@@jincymathewm362 It's a good point. I've intentionally avoided ordinal data in this video because it really is a separate category from a stats perspective and usually requires nonparametric methods. Fortunately IB Bio high schoolers aren't expected to use it!

This helped so much with my research! Thank you :)

Very precise and clear

This video helped me so much. I was struggling really hard with finding the right statistical test for my biology IA. Thank you so much

Great simple. Effective. Video. Love it

Thanks much you ppl are amazing . Helping us biology ppl