Comparing Cats: A Discussion of Similarities & Differences

[Shadow]

This is now somewhat longer text. I might modify it with time to shorter, but now I go with this.


About average weights.

Since there seems to be some disagreement about the way to calculate, I thought to put here some thoughts.


If 15 pieces of something in two groups. Imagine figures as weights or whatever:

Group A, 10 pieces:
(101+150+113+134+120+145+119+131+140+107) Total 1260 and in average 126.

Group B, 5 pieces:
(134+148+159+155+128) Total 724 and in average 144,8

Counting all together, total number would be 1984 and in average 1 piece 132,27

If counting average like this 126+144,8=270,8 and then 270,8:2= 1 piece 135,40

In this case second method to calculate gives bigger and wrong average.


So if this would be calculating average size of fruits from one tree and having 10 fruits from yesterday and 5 fruits from today, it´s clear that right average weight is 132,27
This could be calculated by summing up all individual weights and dividing with total number.
Or (10x126+5x144,8):15 = 132,27. This could be the case if knowing only, that average weight of 10 was 126 and average weight of 5 was 144,8.

If counting 126+144,8:2 it would give that result 135,4, which could be said to be wrong in this case.

But if it would be known, that size and weight of fruits would variate every day. One day giving smaller and another day bigger, while total number would be about the same. Then situation would be a bit different.


So when comparing for instance tigers from place A and place B. If knowing without any doubt, that tigers at place A are bigger than tigers at place B, but could catch from place A for instance 8 tigers and from place B 25 tigers, situation is a bit more complicated.

Here it would be clear, that getting more reliable average weight for population B than for population A. Now if having for population A average of 215 kg and for population B 192 kg it could be said, that average weight of these two populations is 215+192:2= 203,5 kg. It could be said also, that it should be counted (215x8+192x25):33=197,58 kg

If it could be considered for sure, that population A really produce bigger tigers, then I think, that first method is ok and better, average of A + average of B divided with 2

But if there would be no certainty, just finding 8 tigers from A and 25 tigers from B, then second method, because it gives correct average for all.

And again if comparing data from 100 years ago to data from today, then if reasonable sample sizes from both, I would prefer method historical+current and divided by 2 to find out the best estimation of average weight for 100 years of time.

To give one concrete example. If people studying tigers could catch 75 Sundarban tigers with average weight of let´s say 130 kg and then 15 tigers from mainland India with average weight of 202 kg.

One could make a claim, that average weight of Bengal tigers is (75x130+15x202):90= 142 kg.  Another could say, that no, it´s 202+130 divided by 2 and result 166 kg. 

And I would say, that both failing to give right idea of the size concerning vast majority of Bengal tigers even though second method slightly closer.


What I try to say with all that is, that while calculating something is simple, getting the right answer can be way more complicated. There are many factors to consider when trying to be as objective as possible. Sample sizes, time of study, is there real and proven difference in between some populations or not, is some weight information reliable or not really etc.

I personally can´t take too seriously averages, when sample sizes are very small, just a few individuals. When something like 1-3 animals and especially if very similar sized, it´s practically useless. It just gives some idea about what it might be without any certainty.

Closer to ten and smaller and bigger included, then it starts to give at least a reasonable idea.

All in all, weights in this posting are (obviously) just random figures used to clarify things. I hope, that this opens up things and maybe some misunderstandings also can be understood if such have been there. Reply

[Spalea]

(09-25-2020, 12:43 PM)peter Wrote:

(09-24-2020, 07:51 PM)Spalea Wrote: @peter :

About #241...

First of all I don't contest that a tiger could be longer or more athletic than a lion. That isn't the point and the lions have other assets. I just disapprove of the fact to drop a sentence with no one argument to back it up. I should have taken into account the PCKTS's past within Wildfact... Sorry.

Then... As concerns your remarks about my posts... Well, I consider we are in front of a wild life which is going to completely vanish in a mere two or three decades at the most and all of us with it, (the actual covid crisis darkening the picture, parcs keepers and guards without incomes formerly generated by the tourism and leaving the fauna without protection against poaching). In my opinion, these pictures depict a sort of last testimony before becoming some relics of a lost world. Human madness... But ok ! I will try to be more "personal" with an additionnal pinch of salt (rather pepper or spice, without sinking into insults or unwarranted affirmations of course) into my future posts.

Thank you for your suggestions.

My trade is tigers, but that doesn't mean I'm not interested in lions. I often visit the lion section to read. It's the largest section of Wildfact and generates more traffic than all others. You know I was close with Tshokwane, our former lion mod. There was a reason for that. Remember any member disgrading lions one way or another will be noticed and addressed. No worries. 

Agreed with your remarks on the destruction of the natural world and the effect of covid on conservation. Most involved in decisions affecting the natural world and those making their home in that unseen world know about the often devastating effects of their decisions. I'm referring to the situation in the western hemisphere in particular. The time for change has arrived. One can only hope voters realize a very different outlook is needed.   
 
Saw your latest contribution in the Ape thread and liked the extended info and the drawing you added. That is a personal touch.

I know you're interested too in lions, I will never forget your thread #77 about them in the Mapogo lions section:
https://wildfact.com/forum/topic-the-mig...gos?page=6
It's natural to have a preference to one animal or a group of animals. The foulest situation is too read endless debates lion vs tiger where the one's defenders are coming to hate (or despise) the other animal... For this reason one, I react perhaps a little bit too sharply when somebody expresses a categorical assertion with no one argument before and after.
Otherwise, I have to find a new way of operating in this forum: more reading, fewer posts, a good balance... Patience. Reply

[Tigerclaw]

(09-26-2020, 01:21 PM)Shadow Wrote: This is now somewhat longer text. I might modify it with time to shorter, but now I go with this.


About average weights.

Since there seems to be some disagreement about the way to calculate, I thought to put here some thoughts.


If 15 pieces of something in two groups. Imagine figures as weights or whatever:

Group A, 10 pieces:
(101+150+113+134+120+145+119+131+140+107) Total 1260 and in average 126.

Group B, 5 pieces:
(134+148+159+155+128) Total 724 and in average 144,8

Counting all together, total number would be 1984 and in average 1 piece 132,27

If counting average like this 126+144,8=270,8 and then 270,8:2= 1 piece 135,40

In this case second method to calculate gives bigger and wrong average.


So if this would be calculating average size of fruits from one tree and having 10 fruits from yesterday and 5 fruits from today, it´s clear that right average weight is 132,27
This could be calculated by summing up all individual weights and dividing with total number.
Or (10x126+5x144,8):15 = 132,27. This could be the case if knowing only, that average weight of 10 was 126 and average weight of 5 was 144,8.

If counting 126+144,8:2 it would give that result 135,4, which could be said to be wrong in this case.

But if it would be known, that size and weight of fruits would variate every day. One day giving smaller and another day bigger, while total number would be about the same. Then situation would be a bit different.


So when comparing for instance tigers from place A and place B. If knowing without any doubt, that tigers at place A are bigger than tigers at place B, but could catch from place A for instance 8 tigers and from place B 25 tigers, situation is a bit more complicated.

Here it would be clear, that getting more reliable average weight for population B than for population A. Now if having for population A average of 215 kg and for population B 192 kg it could be said, that average weight of these two populations is 215+192:2= 203,5 kg. It could be said also, that it should be counted (215x8+192x25):33=197,58 kg

If it could be considered for sure, that population A really produce bigger tigers, then I think, that first method is ok and better, average of A + average of B divided with 2

But if there would be no certainty, just finding 8 tigers from A and 25 tigers from B, then second method, because it gives correct average for all.

And again if comparing data from 100 years ago to data from today, then if reasonable sample sizes from both, I would prefer method historical+current and divided by 2 to find out the best estimation of average weight for 100 years of time.

To give one concrete example. If people studying tigers could catch 75 Sundarban tigers with average weight of let´s say 130 kg and then 15 tigers from mainland India with average weight of 202 kg.

One could make a claim, that average weight of Bengal tigers is (75x130+15x202):90= 142 kg.  Another could say, that no, it´s 202+130 divided by 2 and result 166 kg. 

And I would say, that both failing to give right idea of the size concerning vast majority of Bengal tigers even though second method slightly closer.


What I try to say with all that is, that while calculating something is simple, getting the right answer can be way more complicated. There are many factors to consider when trying to be as objective as possible. Sample sizes, time of study, is there real and proven difference in between some populations or not, is some weight information reliable or not really etc.

I personally can´t take too seriously averages, when sample sizes are very small, just a few individuals. When something like 1-3 animals and especially if very similar sized, it´s practically useless. It just gives some idea about what it might be without any certainty.

Closer to ten and smaller and bigger included, then it starts to give at least a reasonable idea.

All in all, weights in this posting are (obviously) just random figures used to clarify things. I hope, that this opens up things and maybe some misunderstandings also can be understood if such have been there.

 Hello Shadow...

I think this should be a better example how much the first method falsify the data. (Note: if both datas have the same sample size then the 1st method can be used)
If you have 42 Tigers with a average weight of 190.5 kg and 2 Tiger with a average weight with 245 kg, 6 tigers with a average weight of 216 kg and one tiger with 197 and if we use the first method we get 212 kg for 51 tigers....

with the second method 195.7 kg.

Therefore it was good to take such errors more seriously.

Best regards Reply

[Shadow]

(09-27-2020, 07:17 PM)Tigerclaw Wrote:

(09-26-2020, 01:21 PM)Shadow Wrote: This is now somewhat longer text. I might modify it with time to shorter, but now I go with this.


About average weights.

Since there seems to be some disagreement about the way to calculate, I thought to put here some thoughts.


If 15 pieces of something in two groups. Imagine figures as weights or whatever:

Group A, 10 pieces:
(101+150+113+134+120+145+119+131+140+107) Total 1260 and in average 126.

Group B, 5 pieces:
(134+148+159+155+128) Total 724 and in average 144,8

Counting all together, total number would be 1984 and in average 1 piece 132,27

If counting average like this 126+144,8=270,8 and then 270,8:2= 1 piece 135,40

In this case second method to calculate gives bigger and wrong average.


So if this would be calculating average size of fruits from one tree and having 10 fruits from yesterday and 5 fruits from today, it´s clear that right average weight is 132,27
This could be calculated by summing up all individual weights and dividing with total number.
Or (10x126+5x144,8):15 = 132,27. This could be the case if knowing only, that average weight of 10 was 126 and average weight of 5 was 144,8.

If counting 126+144,8:2 it would give that result 135,4, which could be said to be wrong in this case.

But if it would be known, that size and weight of fruits would variate every day. One day giving smaller and another day bigger, while total number would be about the same. Then situation would be a bit different.


So when comparing for instance tigers from place A and place B. If knowing without any doubt, that tigers at place A are bigger than tigers at place B, but could catch from place A for instance 8 tigers and from place B 25 tigers, situation is a bit more complicated.

Here it would be clear, that getting more reliable average weight for population B than for population A. Now if having for population A average of 215 kg and for population B 192 kg it could be said, that average weight of these two populations is 215+192:2= 203,5 kg. It could be said also, that it should be counted (215x8+192x25):33=197,58 kg

If it could be considered for sure, that population A really produce bigger tigers, then I think, that first method is ok and better, average of A + average of B divided with 2

But if there would be no certainty, just finding 8 tigers from A and 25 tigers from B, then second method, because it gives correct average for all.

And again if comparing data from 100 years ago to data from today, then if reasonable sample sizes from both, I would prefer method historical+current and divided by 2 to find out the best estimation of average weight for 100 years of time.

To give one concrete example. If people studying tigers could catch 75 Sundarban tigers with average weight of let´s say 130 kg and then 15 tigers from mainland India with average weight of 202 kg.

One could make a claim, that average weight of Bengal tigers is (75x130+15x202):90= 142 kg.  Another could say, that no, it´s 202+130 divided by 2 and result 166 kg. 

And I would say, that both failing to give right idea of the size concerning vast majority of Bengal tigers even though second method slightly closer.


What I try to say with all that is, that while calculating something is simple, getting the right answer can be way more complicated. There are many factors to consider when trying to be as objective as possible. Sample sizes, time of study, is there real and proven difference in between some populations or not, is some weight information reliable or not really etc.

I personally can´t take too seriously averages, when sample sizes are very small, just a few individuals. When something like 1-3 animals and especially if very similar sized, it´s practically useless. It just gives some idea about what it might be without any certainty.

Closer to ten and smaller and bigger included, then it starts to give at least a reasonable idea.

All in all, weights in this posting are (obviously) just random figures used to clarify things. I hope, that this opens up things and maybe some misunderstandings also can be understood if such have been there.

 Hello Shadow...

I think this should be a better example how much the first method falsify the data. (Note: if both datas have the same sample size then the 1st method can be used)
If you have 42 Tigers with a average weight of 190.5 kg and 2 Tiger with a average weight with 245 kg, 6 tigers with a average weight of 216 kg and one tiger with 197 and if we use the first method we get 212 kg for 51 tigers....

with the second method 195.7 kg.

Therefore it was good to take such errors more seriously.

Best regards

It´s a valid point to discuss about it, that how average weight should be calculated. These things can be discussed, when it´s done with good argumentation. It´s very clear, that no matter what animals or animal populations we are talking about, sample size of 1-5 isn´t enough to give reliable information for average weight. It´s more something like directional if that is the correct word. It gives just an idea what is maybe possible. So it can´t be evaluated in same way as average which have been got from some reasonable sample size, which should be at least around ten individuals and desirable more. There is too much room for coincidences when just a few individuals.

Naturally problem is, that in some occasions there simply isn´t much reliable data to use. In those cases we have just kind of estimations or guesses.

So when thinking purely mathematically, very small sample sizes are invalid in order to estimate averages for some big number of animals or animal populations. This can´t be denied, imo. 

I don´t think that this kind of thoughts wouldn´t be taken seriously, when discussed in decent way.

This kind of discussions are often poisoned by obvious or hidden agendas of people discussing. People have preset goals and it leads to cherry picking what comes to used data, also to using unreliable information etc. Here first priority has to be reliable data, no matter if it´s possible or impossible to make any conclusions from it. Reply

[tigerluver]

(09-26-2020, 01:21 PM)Shadow Wrote: Here it would be clear, that getting more reliable average weight for population B than for population A. Now if having for population A average of 215 kg and for population B 192 kg it could be said, that average weight of these two populations is 215+192:2= 203,5 kg. It could be said also, that it should be counted (215x8+192x25):33=197,58 kg

The bolded is a weighted average and is the correct way to calculate averages from a pooled sample. Ideally we would also calculate the standard deviation and confidence interval but that requires the individual datapoints unless the source gave the standard deviation somewhere. People will come to find once confidence intervals are applied all the arguments about is the real average is 185 or 195 will be null as... the confidence interval of either value will show there is a 95% chance both these values are reflective of the true population mean. I highly recommend all users interested in average mass to understand confidence intervals and subsequently put their efforts in places where gaps truly do need to be filled. Reply

[Ashutosh]

@tigerluver, I don’t want to step on your toes or anything but the most accurate way would be to calculate average weight based on population percentage rather than number of specimen captured because it gives a much truer representation. It would be like if in India, the parliamentary representative are based upon a particular area size rather than a population size whereby representation will not be equal.

So, there are 3500 Bengal Tigers (India, Nepal, Bhutan, Bangladesh). 210 or 6% are from Sundarbans (India, Bangladesh). Let us assume the average of Sundarbans tiger is 140 kilos, and the average weight of Mainland tigers is 205 kilos, then,

Avg weight of Bengal tiger should be 0.06X140 + 0.94X205 = 201.1

The number of specimens should be used as a better determiner for the average weight of a subpopulation rather than paint a picture which doesn’t take the population factor into account.

Like if we were to break the mainland tiger into Central Indian, Southern Indian, Terai and Assam (these are just broad categories, you could further categorize them or even subcategorize them using the population from individual parks). 

Now we use the same population percentage to give weightage to an average weight of the certain subpopulation to arrive at the final average weight for mainland tigers. Reply

[tigerluver]

(09-28-2020, 03:23 AM)Ashutosh Wrote: @tigerluver, I don’t want to step on your toes or anything but the most accurate way would be to calculate average weight based on population percentage rather than number of specimen captured because it gives a much truer representation. It would be like if in India, the parliamentary representative are based upon a particular area size rather than a population size whereby representation will not be equal.

So, there are 3500 Bengal Tigers (India, Nepal, Bhutan, Bangladesh). 210 or 6% are from Sundarbans (India, Bangladesh). Let us assume the average of Sundarbans tiger is 140 kilos, and the average weight of Mainland tigers is 205 kilos, then,

Avg weight of Bengal tiger should be 0.06X140 + 0.94X205 = 201.1

The number of specimens should be used as a better determiner for the average weight of a subpopulation rather than paint a picture which doesn’t take the population factor into account.

Like if we were to break the mainland tiger into Central Indian, Southern Indian, Terai and Assam (these are just broad categories, you could further categorize them or even subcategorize them using the population from individual parks). 

Now we use the same population percentage to give weightage to an average weight of the certain subpopulation to arrive at the final average weight for mainland tigers.

This is an interesting point, I like it. However the current sample sizes are so small that one would be making heavy assumptions using this method. In other words, the sample sizes are so small that those percentages could be a priori. And the next issue is if two populations are that different, is there any point in averaging them together? We use averages to describe a population composed of similar individuals. Averaging a Sunderban tiger with a central Indian tiger results in an average that reflects an imaginary population that doesn’t exist. I know in forums people like averages to come up with numbers on essentially imaginary animals that don’t exist to support their points. The tiger is known as the largest cat not because its theoretical/imaginary average is the highest (the imaginary subspecies averaged tiger is not), but because its largest scientifically published population is about 20% heavier than the largest population of the penultimate species in mass. Reply

[Rishi]

(09-28-2020, 04:20 AM)tigerluver Wrote:

(09-28-2020, 03:23 AM)Ashutosh Wrote: @tigerluver, I don’t want to step on your toes or anything but the most accurate way would be to calculate average weight based on population percentage rather than number of specimen captured because it gives a much truer representation. It would be like if in India, the parliamentary representative are based upon a particular area size rather than a population size whereby representation will not be equal.

So, there are 3500 Bengal Tigers (India, Nepal, Bhutan, Bangladesh). 210 or 6% are from Sundarbans (India, Bangladesh). Let us assume the average of Sundarbans tiger is 140 kilos, and the average weight of Mainland tigers is 205 kilos, then,

Avg weight of Bengal tiger should be 0.06X140 + 0.94X205 = 201.1

The number of specimens should be used as a better determiner for the average weight of a subpopulation rather than paint a picture which doesn’t take the population factor into account.

Like if we were to break the mainland tiger into Central Indian, Southern Indian, Terai and Assam (these are just broad categories, you could further categorize them or even subcategorize them using the population from individual parks). 

Now we use the same population percentage to give weightage to an average weight of the certain subpopulation to arrive at the final average weight for mainland tigers.

This is an interesting point, I like it. However the current sample sizes are so small that one would be making heavy assumptions using this method. In other words, the sample sizes are so small that those percentages could be a priori. And the next issue is if two populations are that different, is there any point in averaging them together? We use averages to describe a population composed of similar individuals. Averaging a Sunderban tiger with a central Indian tiger results in an average that reflects an imaginary population that doesn’t exist. I know in forums people like averages to come up with numbers on essentially imaginary animals that don’t exist to support their points. The tiger is known as the largest cat not because its theoretical/imaginary average is the highest (the imaginary subspecies averaged tiger is not), but because its largest scientifically published population is about 20% heavier than the largest population of the penultimate species in mass.

Yeah, that's why WII uses weight range now (like that 200-260) Jhala told about tigers & (160 to 200) for Asian lions. It's where you'd expect atleast 50% of the healthy adults, not some average... I think that's a much more prudent method.
Especially because even a single animal has its weight fluctuating almost 50lbs though the seasons.

Then you've got several other factors like regional variations, age & health conditions, or much of the weighed specimens being problem animals for both species in India atleast. Reply

[Pckts]

Reply

[Shadow]

(09-28-2020, 06:41 AM)Rishi Wrote:

(09-28-2020, 04:20 AM)tigerluver Wrote:

(09-28-2020, 03:23 AM)Ashutosh Wrote: @tigerluver, I don’t want to step on your toes or anything but the most accurate way would be to calculate average weight based on population percentage rather than number of specimen captured because it gives a much truer representation. It would be like if in India, the parliamentary representative are based upon a particular area size rather than a population size whereby representation will not be equal.

So, there are 3500 Bengal Tigers (India, Nepal, Bhutan, Bangladesh). 210 or 6% are from Sundarbans (India, Bangladesh). Let us assume the average of Sundarbans tiger is 140 kilos, and the average weight of Mainland tigers is 205 kilos, then,

Avg weight of Bengal tiger should be 0.06X140 + 0.94X205 = 201.1

The number of specimens should be used as a better determiner for the average weight of a subpopulation rather than paint a picture which doesn’t take the population factor into account.

Like if we were to break the mainland tiger into Central Indian, Southern Indian, Terai and Assam (these are just broad categories, you could further categorize them or even subcategorize them using the population from individual parks). 

Now we use the same population percentage to give weightage to an average weight of the certain subpopulation to arrive at the final average weight for mainland tigers.

This is an interesting point, I like it. However the current sample sizes are so small that one would be making heavy assumptions using this method. In other words, the sample sizes are so small that those percentages could be a priori. And the next issue is if two populations are that different, is there any point in averaging them together? We use averages to describe a population composed of similar individuals. Averaging a Sunderban tiger with a central Indian tiger results in an average that reflects an imaginary population that doesn’t exist. I know in forums people like averages to come up with numbers on essentially imaginary animals that don’t exist to support their points. The tiger is known as the largest cat not because its theoretical/imaginary average is the highest (the imaginary subspecies averaged tiger is not), but because its largest scientifically published population is about 20% heavier than the largest population of the penultimate species in mass.

Yeah, that's why WII uses weight range now (like that 200-260) Jhala told about tigers & (160 to 200) for Asian lions. It's where you'd expect atleast 50% of the healthy adults, not some average... I think that's a much more prudent method.
Especially because even a single animal has its weight fluctuating almost 50lbs though the seasons.

Then you've got several other factors like regional variations, age & health conditions, or much of the weighed specimens being problem animals for both species in India atleast.

Even though we can´t stop the discussion about sizes and overlapping in between some species. Obviously especially in between tigers and lions because they are so close to each others in size, it´s good to talk about it, that what some things mean and what is behind some figures. Like this weight range, that 200-260 means, that at least 50% of the healthy adults are inside that range. Otherwise there is soon someone saying: "NOOOOOOO, that´s wrong, there was this and that tiger weighing less or a bit more".

Then we have scientific studies giving somewhat different conclusions, as usually, depending what they have accepted to be useful data. 

Then again there is situation in captivity, which show maybe closer call than situation in wild.

So while this kind of discussion is like walking on the swamp, getting one step to somewhat solid ground and sinking with next one, it´s good if people at least understand what some figures mean and in what way calculations have been made. In that way it can be seen how different data should be compared or can it be compared at all.

Problem in this ongoing conversation here and there is, that often there are people preferring tigers trying to exaggerate data concerning tigers and then people preferring lions with the goal to exaggerate lions. And whenever these people see something they don´t like, accusations start. I hope, that the more people understand how some data is used and in what way charts are made, the less there are misunderstandings. Both by accident and on purpose.

These are two species overlapping quite a lot in size, it´s kind of odd how big emotions are involved so often when discussing about them. But hopefully this latest discussion has given some understanding how some figures should be understood. Reply

[Rishi]

(09-28-2020, 04:32 PM)Shadow Wrote:

(09-28-2020, 06:41 AM)Rishi Wrote: Yeah, that's why WII uses weight range now (like that 200-260) Jhala told about tigers & (160 to 200) for Asian lions. It's where you'd expect atleast 50% of the healthy adults, not some average... I think that's a much more prudent method.
Especially because even a single animal has its weight fluctuating almost 50lbs though the seasons.

Then you've got several other factors like regional variations, age & health conditions, or much of the weighed specimens being problem animals for both species in India atleast.

Even though we can´t stop the discussion about sizes and overlapping in between some species. Obviously especially in between tigers and lions because they are so close to each others in size, it´s good to talk about it, that what some things mean and what is behind some figures. Like this weight range, that 200-260 means, that at least 50% of the healthy adults are inside that range. Otherwise there is soon someone saying: "NOOOOOOO, that´s wrong, there was this and that tiger weighing less or a bit more".

Then we have scientific studies giving somewhat different conclusions, as usually, depending what they have accepted to be useful data. 

Then again there is situation in captivity, which show maybe closer call than situation in wild.

So while this kind of discussion is like walking on the swamp, getting one step to somewhat solid ground and sinking with next one, it´s good if people at least understand what some figures mean and in what way calculations have been made. In that way it can be seen how different data should be compared or can it be compared at all.

Problem in this ongoing conversation here and there is, that often there are people preferring tigers trying to exaggerate data concerning tigers and then people preferring lions with the goal to exaggerate lions. And whenever these people see something they don´t like, accusations start. I hope, that the more people understand how some data is used and in what way charts are made, the less there are misunderstandings. Both by accident and on purpose.

These are two species overlapping quite a lot in size, it´s kind of odd how big emotions are involved so often when discussing about them. But hopefully this latest discussion has given some understanding how some figures should be understood.

My post wasn't related to comparison of species though, just the comparison of methodology. Reply

[Shadow]

(09-28-2020, 04:54 PM)Rishi Wrote:

(09-28-2020, 04:32 PM)Shadow Wrote:

(09-28-2020, 06:41 AM)Rishi Wrote: Yeah, that's why WII uses weight range now (like that 200-260) Jhala told about tigers & (160 to 200) for Asian lions. It's where you'd expect atleast 50% of the healthy adults, not some average... I think that's a much more prudent method.
Especially because even a single animal has its weight fluctuating almost 50lbs though the seasons.

Then you've got several other factors like regional variations, age & health conditions, or much of the weighed specimens being problem animals for both species in India atleast.

Even though we can´t stop the discussion about sizes and overlapping in between some species. Obviously especially in between tigers and lions because they are so close to each others in size, it´s good to talk about it, that what some things mean and what is behind some figures. Like this weight range, that 200-260 means, that at least 50% of the healthy adults are inside that range. Otherwise there is soon someone saying: "NOOOOOOO, that´s wrong, there was this and that tiger weighing less or a bit more".

Then we have scientific studies giving somewhat different conclusions, as usually, depending what they have accepted to be useful data. 

Then again there is situation in captivity, which show maybe closer call than situation in wild.

So while this kind of discussion is like walking on the swamp, getting one step to somewhat solid ground and sinking with next one, it´s good if people at least understand what some figures mean and in what way calculations have been made. In that way it can be seen how different data should be compared or can it be compared at all.

Problem in this ongoing conversation here and there is, that often there are people preferring tigers trying to exaggerate data concerning tigers and then people preferring lions with the goal to exaggerate lions. And whenever these people see something they don´t like, accusations start. I hope, that the more people understand how some data is used and in what way charts are made, the less there are misunderstandings. Both by accident and on purpose.

These are two species overlapping quite a lot in size, it´s kind of odd how big emotions are involved so often when discussing about them. But hopefully this latest discussion has given some understanding how some figures should be understood.

My post wasn't related to comparison of species though, just the comparison of methodology.

Yes, but it´s something very relevant to understand for people who see information and try to understand what they see in different places. Many misunderstandings are based on it, that there isn´t too much knowledge how to render different figures. So it´s good to open up, like you did, how WII uses weight ranges. Many people seem to just look quickly numbers, not so much what is written before or after. Reply

[GuateGojira]

About methods and averages:

Resently there is a confusion about the methods used in the averages, specially by people that is "new" on the business. I will try to share a light on this point.

Before to start, please check this information, in post No. 361: https://wildfact.com/forum/topic-modern-...rs?page=25
This is about the problems in using old data and the reliability of the figures uses on averages.

Also this link in the post 390: https://wildfact.com/forum/topic-modern-...rs?page=26
This is about the exceptional specimens, and this most be applied to lions too, specially with those two obscure figures of 750 and 800 lb from two lions quoted in a newspaper that is more unreliable than the old figures from Amur tigers of Baikov.

Ok, lets fo to the main point:

The method that all of us is using since the old days of AVA since year 2003 is the "simple average" of all the figures available. Is the easiest and faster of all the methods. We only need to take all the figures available and make an average, simple as it is. Now, the issue is when we don't have the single figures but only averages and this is an issue that we found specially with some lion and tiger populations. So, what we have done is just to make the simple average of all the average figures and get a result, we know that this is not perfect but has been used and provided reliable results since those days. Now, I see that two posters (one of them banned twice) insist in put doubt about the reliability of the method and suggest changes, but how reliable are those changes? Are they necesary? Will they produce different results?

The first person that tried to provide other method was, as far I remember, @tigerluver in the AVA forum and he proposed the "weighted average", which means to include the "weight" of each value in the population. This means to take in count the size of the sample used, but that method was actually never used in any of the calculations until this day. @Shadow explained in this moment his opinion about the importance of its aplication, but the issue here is that we are normally using small samples and that is a fact that we can't avoid and some people had used this as an excuse to label the samples as "unreliable" just because do not fit they "agendas". Even using all those values we had never reached samples that actually represent the entire populations. Interesting while this is an "issue" for the fans at forums, while it is something that do not disturb the real scientists to much, as they know how dificult is to collect the morphological information of wild animals. So how reliable is to use just 3 tigers from a population of at least 40, at the end the weighed of the values by the sample size will also provide results that are not 100% true.

Now, the other method that I tried to use is the "weighted average" using the value of the size of the populations like @Ashutosh mentioned. In fact, I tried to weight the average figures with the representative size that each group means for the entire population. For me that will be more "reliable", but the issue is that we do not have historic information about the population size of each region, so we can use the last information provided by the census made in modern years, but that will represent the tiger population at 2010 or 2014, not the population at 1900 for example. Other problem is how relaible are the population figures? Check how many times the figures of Sundarbans had been inflated from 100 to over 400 animals! I am aware of this because Dr Karanth had mentioned this many times. On the other side check the values from Nepal and Russia, which are more reliable and based only in adults specimens. So, also using population figures will create problems.

As we can see, using any of the methods proposed at the end there are problems that will cause bias in the results, even when we try to make it the most accuarate possible and this is NOT something new. Those that actually followed these debates that started in AVA knows that the results are allways debated because there is an external group of crazy and immature people that still want to continue with the "Lion-vs-Tiger" debate, specially with a group of 3-4 lion fanatics that at this day still insist in presenting results that are biased and completelly unreliable. Sadly, these new posters do not know the history behind all this efforts in presenting information and reliable/unbiased results and only critize without knowing that there is a big history behing all this.

So, knowing this, it is reliable to use the "weighted average"? Well, the funny thing is that I made it with the Bengal tigers and the average of all the populations (n=166, including Sundarbans) is of 200.3 kg, just 3 kg more than the simple method. But remember that it is now stablished that the samples includes several subadults tigers from 150 - 180 kg that were included by hunters in they records, so that is why I estimated a figures of c.200 kg for Bengal tigers overall, including Sundarbans and also the subadults (if some one insist in using my old paper from from 2010 or 2015, I don't even remember, know than that paper os OLD and do not have all the new specimens that I have now, so don't insist in using old information to battle with the new reults). When I made this to the lions, the figure of the lions from Botswana changed from 184 to 190 kg, but the figures from Namibia also changed from 197 to 190 kg, so it standarized all the values for the lions in Southern Africa at c.190 kg, but the figures of the lions from East Africa droped fom 174 to 173 kg. So, if there is a person there tryting to diminish the weight of the tigers using this method, actually is the one of the lions that will result in even more diminishing.

Now, how necesary is the use of these methods to stablish the averages? Is this even this important? Well it seems that for people like Dr Yamaguchi it is not, and we can see this in the book from 2010 (Chapter 4) "Tigers of the Woeld" when he says that in order to calculate the average at species level he used only the simple average of all the subspecies or populations, he did not made any "weighed average" or a "population weighing", he just put the values and made a simple average of averages, and incredible my values match those from him.

Other thing is that other experts only used ranges and not averages, which is a lot easier and we can see this with Mazák, Karanth and Jhala, which do not botter to make all these calculations, they only stablished ranges and that was all.

Finaly, is actually the "average" the most important measurement? I think not entirelly, because also the Mode is a very imporatant value that is completelly forgoten in all these studies and debates. I noted this situation when I investigated the size of the orca and I found that the mode was used in several of the studies, showing how important it is. Check this image, is self explanatory:

*This image is copyright of its original author

In this case the mode is fundamental, as it will show to us wich is the most common weight in a population. Now the problem here is that we can't use it in all the populations because in some cases, like Brander or Smuts, we only know the averages, ranges and sample sizes.

So, what I am going to do? Been honest, NOTHING. In this mometn I don't have the time to enter in this type of futile discutions, so I will leave this to you, the "experts" that want to make the difference, so you can discuss, fight, insult, and walk aaaaalllllllllllll the way to here that the old posters had already done, and when you get to a conclution with VALID arguments, call me again and I will recalculate the figures with this proposed new method, ok? But take in count that we are working in some cases with only average figures and samples and in other cases (the good ones) we have the all single values.

If some one here gets offended with my words, please know that it is not my intention, but understand that in this moment I am really tired of this back and forth with the same thing again and again and again, and I will want to finish this thing of the sizes ones for all (that was the objective of the comparative images after all).

So call me when you are ready, then we will talk about this again. 

Good night. Reply

[Shadow]

(10-06-2020, 10:46 AM)GuateGojira Wrote: About methods and averages:

Resently there is a confusion about the methods used in the averages, specially by people that is "new" on the business. I will try to share a light on this point.

Before to start, please check this information, in post No. 361: https://wildfact.com/forum/topic-modern-...rs?page=25
This is about the problems in using old data and the reliability of the figures uses on averages.

Also this link in the post 390: https://wildfact.com/forum/topic-modern-...rs?page=26
This is about the exceptional specimens, and this most be applied to lions too, specially with those two obscure figures of 750 and 800 lb from two lions quoted in a newspaper that is more unreliable than the old figures from Amur tigers of Baikov.

Ok, lets fo to the main point:

The method that all of us is using since the old days of AVA since year 2003 is the "simple average" of all the figures available. Is the easiest and faster of all the methods. We only need to take all the figures available and make an average, simple as it is. Now, the issue is when we don't have the single figures but only averages and this is an issue that we found specially with some lion and tiger populations. So, what we have done is just to make the simple average of all the average figures and get a result, we know that this is not perfect but has been used and provided reliable results since those days. Now, I see that two posters (one of them banned twice) insist in put doubt about the reliability of the method and suggest changes, but how reliable are those changes? Are they necesary? Will they produce different results?

The first person that tried to provide other method was, as far I remember, @tigerluver in the AVA forum and he proposed the "weighted average", which means to include the "weight" of each value in the population. This means to take in count the size of the sample used, but that method was actually never used in any of the calculations until this day. @Shadow explained in this moment his opinion about the importance of its aplication, but the issue here is that we are normally using small samples and that is a fact that we can't avoid and some people had used this as an excuse to label the samples as "unreliable" just because do not fit they "agendas". Even using all those values we had never reached samples that actually represent the entire populations. Interesting while this is an "issue" for the fans at forums, while it is something that do not disturb the real scientists to much, as they know how dificult is to collect the morphological information of wild animals. So how reliable is to use just 3 tigers from a population of at least 40, at the end the weighed of the values by the sample size will also provide results that are not 100% true.

Now, the other method that I tried to use is the "weighted average" using the value of the size of the populations like @Ashutosh mentioned. In fact, I tried to weight the average figures with the representative size that each group means for the entire population. For me that will be more "reliable", but the issue is that we do not have historic information about the population size of each region, so we can use the last information provided by the census made in modern years, but that will represent the tiger population at 2010 or 2014, not the population at 1900 for example. Other problem is how relaible are the population figures? Check how many times the figures of Sundarbans had been inflated from 100 to over 400 animals! I am aware of this because Dr Karanth had mentioned this many times. On the other side check the values from Nepal and Russia, which are more reliable and based only in adults specimens. So, also using population figures will create problems.

As we can see, using any of the methods proposed at the end there are problems that will cause bias in the results, even when we try to make it the most accuarate possible and this is NOT something new. Those that actually followed these debates that started in AVA knows that the results are allways debated because there is an external group of crazy and immature people that still want to continue with the "Lion-vs-Tiger" debate, specially with a group of 3-4 lion fanatics that at this day still insist in presenting results that are biased and completelly unreliable. Sadly, these new posters do not know the history behind all this efforts in presenting information and reliable/unbiased results and only critize without knowing that there is a big history behing all this.

So, knowing this, it is reliable to use the "weighted average"? Well, the funny thing is that I made it with the Bengal tigers and the average of all the populations (n=166, including Sundarbans) is of 200.3 kg, just 3 kg more than the simple method. But remember that it is now stablished that the samples includes several subadults tigers from 150 - 180 kg that were included by hunters in they records, so that is why I estimated a figures of c.200 kg for Bengal tigers overall, including Sundarbans and also the subadults (if some one insist in using my old paper from from 2010 or 2015, I don't even remember, know than that paper os OLD and do not have all the new specimens that I have now, so don't insist in using old information to battle with the new reults). When I made this to the lions, the figure of the lions from Botswana changed from 184 to 190 kg, but the figures from Namibia also changed from 197 to 190 kg, so it standarized all the values for the lions in Southern Africa at c.190 kg, but the figures of the lions from East Africa droped fom 174 to 173 kg. So, if there is a person there tryting to diminish the weight of the tigers using this method, actually is the one of the lions that will result in even more diminishing.

Now, how necesary is the use of these methods to stablish the averages? Is this even this important? Well it seems that for people like Dr Yamaguchi it is not, and we can see this in the book from 2010 (Chapter 4) "Tigers of the Woeld" when he says that in order to calculate the average at species level he used only the simple average of all the subspecies or populations, he did not made any "weighed average" or a "population weighing", he just put the values and made a simple average of averages, and incredible my values match those from him.

Other thing is that other experts only used ranges and not averages, which is a lot easier and we can see this with Mazák, Karanth and Jhala, which do not botter to make all these calculations, they only stablished ranges and that was all.

Finaly, is actually the "average" the most important measurement? I think not entirelly, because also the Mode is a very imporatant value that is completelly forgoten in all these studies and debates. I noted this situation when I investigated the size of the orca and I found that the mode was used in several of the studies, showing how important it is. Check this image, is self explanatory:

*This image is copyright of its original author

In this case the mode is fundamental, as it will show to us wich is the most common weight in a population. Now the problem here is that we can't use it in all the populations because in some cases, like Brander or Smuts, we only know the averages, ranges and sample sizes.

So, what I am going to do? Been honest, NOTHING. In this mometn I don't have the time to enter in this type of futile discutions, so I will leave this to you, the "experts" that want to make the difference, so you can discuss, fight, insult, and walk aaaaalllllllllllll the way to here that the old posters had already done, and when you get to a conclution with VALID arguments, call me again and I will recalculate the figures with this proposed new method, ok? But take in count that we are working in some cases with only average figures and samples and in other cases (the good ones) we have the all single values.

If some one here gets offended with my words, please know that it is not my intention, but understand that in this moment I am really tired of this back and forth with the same thing again and again and again, and I will want to finish this thing of the sizes ones for all (that was the objective of the comparative images after all).

So call me when you are ready, then we will talk about this again. 

Good night.

@GuateGojira  I pointed out it, that from small samples it´s not possible to calculate reliable averages for anything. Sample sizes of 1-5 can be used to calculate average for something, but it isn´t reliable. I explained in my posting what kind of problems it can create and it´s obvious.

Naturally in different discussion forums certain methods can be used and it´s what people do, but it doesn´t take out the problem. When sample size of some population is very small, there is no point to try to calculate average weight for that population at all, because the best what can come out from such is very rough estimation what it can be or not. I don´t care where some information comes if I notice that it has a valid point and can´t be ignored.

Why I posted about it was, that many times people discuss about weights and averages and it´s good to open up those things to people so, that they understand how things are calculated and what good and bad things are involved to different methods. Not all pay attention so much, so I think, that it´s good to have discussions time to time. Then people can evaluate in better way information and what they see . Tigers aren´t only species with some grey areas what comes to published weights and there are many kind of estimations based on calculations from different people.

I would point out to people that they would pay attention especially to it, from what information those calculations are made of. I have seen, that you use reliable data, even though it can be discussed how some averages are calculated. Then again there are many people mixing up unreliable data to reliable in order to get the results they are aiming to and that is a totally different thing. It is what I meant in my postings by it, that some people are poisoned with preset agendas. Reliable data used is the most important thing after all. No matter what kind of conclusions from it can or can´t be done.


Ps. One thing to think to all here when posting. Here are people from some old forums and/or existing ones, like AVA. Then again those forums as far as I know are places in which a limited number of people discuss about animals in more or less decent ways. Wildfact has had now over 20 million views. I would bet that a lot of visitors are like me, who had never even heard about AVA or tapatalk and who knows what there are. So whatever has been discussed in past in other forums can be totally unknown to most visitors who have noticed this place and looking what can be found.

My approach can be somewhat different because of it. I didn´t know any posters here in anyway, when I joined wildfact. And I haven´t used time to learn later either, what people have discussed in other forums too much. Some glimpse here and there to understand a bit better why some topics are so "difficult" to discuss in decent way also here and why moderation is needed.

Still I approach things trying to keep in mind how someone new (what comes to visiting wildfact) can see things and what he/she is hoping to find when visiting wildfact. I don´t care so much what people preferring tigers or lions etc. hope to see, there are plenty of forums for people who like to praise one species with people who like the same species and not anything else. Sadly if asked from me.

So if and when posters here want to share information, it should be clear in mind to whom trying to talk about. I think that main target should be new visitors who are genuinely interested to learn. It means questions time to time. We can´t expect, that people would first read all what is written in some other forum during years, especially when a lot of those forums are endless debates, cursing and insulting making it impossible for anyone sane to read more than a few messages before finding something better to do.

And in wildfact situation is also it, that many threads are very long and not realistic to wait, that new members or random visitors would read all. I have hoped, that before posting new members would check at least some latest pages from that thread before posting so that not starting again some discussion which was just ended a week or month ago unless something truly new and relevant to say.

It´s understandable, that sometimes old members feel frustrated, it happens. Still we all have to be ready to discuss about things we write here, one thing which can´t be avoided in public forum :) Reply

[Balam]

To add a few points to these discussion since I've been involved in calculating averages for jaguar populations as well, and something I said in the jaguar thread, is that averages are never written in stone and will always vary according to the sample size one happens to collect or find for it. At one point an average might yield X results, but later new data can be found that can drastically alter said average. That's why I agree with Guate that the mode is a more important factor to consider when looking at weight data because it allows us to see the frequency in which a specific species or population was able to yield a specific weight value at a certain age (assuming the age is included for a decent amount of weights). 

Overall there is no point in obsessing over averages and hope to find the perfect value that will represent a species. Variations among individuals and populations that are affected by external factors across time will inevitably change the average gathered at a different time.

It's best simply to try to get as much data as possible and present an updated and reliable exposition of what the morphology of a specific species/population looks like for readers who are interested to get informed. 

In my personal view, most of the people I have seen who obsess over averages come from animal match up forums who simply want to get a specific value to compare with another animal and then assume the larger will defeat the smaller one. The readership on this forum, however, is more mature and values different things, so it's best not to succumb to external pressures and instead keep providing and collecting as much reliable data as possible for the readers to get access to. Reply