Do men and women economists choose the same fields of research?
Do men and women economists choose the same fields of research?
Economists choose different fields of research according to whether they are men or women. Women tend to favour areas such as health, education, employment and the economics of development, whereas they neglect economic theory, econometrics and finance. Why are there these gender differences in the way in which we invest in the specialisation of our own human capital? And are these differences diminishing over time?
that major issue is why is it so why is it that men and women having the same job I interested in different things women seem to be interested in health family economy services welfare and then econometrics measurement problems quantification of economic variables these are the topics or subjects which are more interesting for men of course we have to ask ourselves a much more wide-ranging question why is it so that women economists seem to disappear when approaching the top level in the academic world if we got hundreds of top level scientists were goes to 15 women and 85 men but if we consider the student population they often females I'm a numerous out of hundred students fifty-four are women and these proportions remain the same until the stage of PhD so it is interesting to understand why do women disappear at the highest levels of a scientific career we have one whole day the Lord Buddha also he is a professor at the Carlos Tercero University in Madrid he got a PhD in Oxford and has been focusing for a long time on labor economics econometrics economic theory he has also been focusing on make economic aspects his areas of interest are partially male econometrics for instance and partially female labor economy for instance I'm sure that Professor Toledo can really help us in answering the questions have just asked he will help us understand the reasons leading to different interests for men and women in the framework of the same profession it is important to understand what are the reasons underlying there is differences choices and Basic Conditions have an impact on the career paths of both men and women I'm sure that professor de lado will provide us with provocative and interesting answers I'm happy to see that we have an audience sir crowded with young people who are just starting their personal career the ladder you have the floor how far my tango and we always admire a lot of Italians for their innovative spirit I mean we always believe that you punish yourself a lot that you are too Alto critical you always win the world champion championship you organize the best events and we really feel very very amused however turning to the topic of my of my talk today I want to share with you some ongoing research I'm doing about a topic which is a rather fashionable it's been going on for for many years which is gender differences the difference between men and women there is a lot of work on differences in wages differences in promotions career differences etc etc but much less on differences in the topics on which researchers in particular fields work so the question I want to address today is whether the data backs up belief in generally spread among our profession economies which is that women tend to be concentrated in the specific fields for instance the media start with the sentence by a very well-known labor economist which basically says that in the 60s and 70s a really large part of the still small representation of female economies we're doing research in specific topics like label household economics a labor supply development etc but the things are changing but this is just a belief there was no evidence about that and what I want to do today is just to argue that this belief is correct but I want to go a step beyond and I want to to give an interpretation to why this distribution of interests of preferences happens in reality and furthermore if I have time and I hope so I want also to share with you the idea that believes self self-fulfilled prophecy prophecies are is a very important aspect in explaining gender differences why people with accept accept the general equally talented etc end up in in a different equilibrium in a different achievement and what policies are more effective to to fight that ok so let me just start by saying that I'll start with some motivation some very basic hypothesis yes to interpret the results give you couple of lines about the data using some empirical evidence and some conclusions and a further further research there is a very large literature not only in economics about the whereabouts of men and women as I said wages promotion publications etcetera etcetera for instance I was asking the chairwoman whether in Italy there is something which it's been going on in the States for many year which is a committee which studies the status of women in the economics profession and in several professions they follows this women this is called the Committee on the status of women in the economic profession there is one also for the European Economic Association even in the Spanish economic Association we have something called cosmic committee the segi me enter de la mujer de economía so before we make reports on how women are are doing however there is very little evidence on topics that they do research on in other sciences is evidence that there for instance in medicine that women are concentrated in particular fields like for instance of state Rick's Pediatrics a lot of women there but very few in surgery so you have to get the surgical operation you have very low probability of getting getting operated by by a woman the same happens for instance in psychology environmental and clinic psychology are female fields whereas for instance neuropsychology is a completely male field and this morning I was also talking to an Italian professor of law he told me that also in low there are female fields in physics etcetera etcetera this is to my knowledge the best the first attempt just to understand what is going on there's another paper which is quoted there for those who are interested which is an auto ship do women economies write more with women or with men and the results are a fairly similar that is women like to work with women rather than with men which is one of the results of the paper okay so in order to interpret in order to interpret the gender segregation or gender differences let's move to occupations and let's see what the literature has told us about potential different potential explanations and later on we'll move to a specific occupation which is research right and see how these explanations can can help to understand it the first one is that there are differences in ability in talent that the brain of the man is not the same as the brain of a of the woman that women are maybe worse for abstract thinking and more able for other activities most of a what the neural neurologists are telling us about is that these differences of metemma okay so I'm going to take the approach that basically the distribution of talents is the same that we are equally capable just as a as a working hypothesis the second one is discrimination okay so we many women feel that they are discriminated that they get over salaries for the same jobs with the same skills etc etc but remember discrimination can only survive in an environment which is non-competitive suppose you are the owner of a football club and then you don't want to buy let me give a name which is familiar to me Ronaldinho because his back you don't like blacks of course if I was playing on my if I if this was the only team in the world then of course nothing would happen Ronaldinho would be would not be my team but if there is competition there would be another team will come get Ronaldinho will play in the Champions League or whatever they will run a linear who will score 10 goals against my team will be relegated will lose a lot of money so whenever competition operates discrimination sort of disappears bland concept therefore research in principle is a highly competitive field particularly if you look at the best institutions if you look at the top 50 universities teaching economics in the world these are institutions which are fighting to attract the best students all over the world because this is the way to perpetuate their prestige etc so I'm going to argue that discrimination for this particular aspect is not so important because I'm selecting a highly competitive field there is also the issue of a self selection so there is an aspect where women and men are different which is that the women have some physical traits which give them some little comparative advantage at the nurturing bearing children and of course they they are the ones who bring children to to this world so suppose that career interruption say for maternity leaves etc is Spanish then women will anticipate this and will say select occupations where these interruptions are not penalized or not so heavily penalized for instance women would like to be civil servants they would like to work in the public sector where rather than in the private sector because if we tell if you tell your boss that you're pregnant and you're going to have a baby you are in danger of getting dismissed right so this is a self-selection it's not different in ability that I select myself for a career which is flatter which say it's more secure it's a baby job for life but very little promotion prospects etc that's a possibility so in terms of research you may think that you may self select two fields which are more mature where you are not going to be one of the superstars in the world but when you publish a little bit you could get tenure in a sort of second order second division University etcetera survive then of course even if we screw that think of the women who are we are going to study these are women with pcs in the best schools in the world who have done a bigger for big accumulation of human capital they just want to succeed they don't want to be in mediocre places they just really want to get to the top so I don't think the third one is so important I did however let me just anticipate as I started with a quote of this labor economist that women are concentrated in certain fields at least according to this the numbers I'm going to show you there is a two possibilities one is that women are excluded by men that is that men avoid women all that women avoid men that this men around the first explanation which is the fourth one has been applied for instance by economists and sociologists or to racial segregation so the idea is that suppose let me just use the the racial segregation example because I think it's very loose dated suppose you have a neighborhood which were only whites work live there well they only leave their office and in some blacks arrive nothing happens they get integrated certain black population lives there but eventually they reach a certain threshold say twenty percent of the population for whatever reasons this is considered by the white population as too much what happens is that the white population leaves that neighborhood that area and it becomes hundred percent black so the in English they have this name called tipping segregation in area which was completely white becomes completely flat we know of many areas in the cities in the in the metropolitan areas etc where this has happened which were white areas are now have began immigrants areas of different ethnic origins so this could be the case for instance in research if some topics are believed to be female topics they are somewhat a stigmatize for instance people think that if you work on a female topic you will get a lower wage or you will get a lower proportion probability or whatever they are stigmatized and men leave the field when there are too many women in there that's one possibility so this is what I will refer to as main avoiding women then there is a second possibly a fifth possibility a second possibility within this a set of explanation which is that women avoid men so there is a lot of experimental psychological literature stress in the fact that it seems that the women who are equally talented as men and us and they know that I'm gonna give you a brief example don't like to compete with men it's not that they don't like competition they like to compete with women but not with men let me just stress that in all these experiments women are perfectly informed and they know they are as good as men so it's not that they are discounted that they are inferior in some activity and since effort is closely why should they exert any effort no no this is yes that they dislike to compete with men they don't want to take part in this sort of macho competition type of thing okay so if this is the case then women will avoid men they would like us to compete with women the example I just want to briefly give you it's an example where three economies I went to a school took a boys and girls of the same age made them they were like four hundred students made them run a certain distance a four hundred meters or 300 meters several times just to take the average time in so just to make sure that it wasn't that they had a bad day or whatever and then chose kids of the same age more or less the same height etc and put them together okay so if you put two boys together who had done the same time or approximately the same time on on their own then there is a tournament effect if that is the fact that you are fighting against another one competing and is the other one when you have service that both kids did a better time than where they were running on their own you put two girls they say happen if you put a boy and a girl the girl used did much worse time that was he were running on her own whereas the boy would do better a better time and this sort of experiment has been repeated in many many instances doing sort of a little mathematical operations many many instances that it eats on like that okay so maybe it's a matter of testosterone or evolution or whatever but the women don't like to compete with me okay so well once I have anticipated all these say all these theories let me just stress a few hypotheses that I wanted to test with the data both the theory of social exclusion which is the one where men avoid women or the theory of the Ender differences in competition and using this acronym as E and GDC where women avoid men just predict that there is going to be some sort of persistence that women will end up where women were before right so for instance in the case of social exclusion suppose you have a field where there is 15% of women all of a sudden is because 100 because male men don't work any longer than that or in the case of female of women avoiding men what we will happen is that women will only go to women are okay so you will have like a sort of persistence there are other aspects which can also be studied so we'll try to discriminate between these two the other aspect is the dimension and the quality of a field so suppose you are working in a field which is large or just to get to fix your attention suppose you run in a big department what will happen in a big department you have a lot of disciplines it's big its large therefore if women like to work with women then they are gonna find this here accommodation in large department that in a small department which is only specialized in a couple of three fields therefore in large department the fraction the percentage of women according to these theories would be large right will be larger because they can find they can diversify more right they say just like the thermal risk return trade-off if you if you have a portfolio asset with many assets then you kind of set some going up some going down if you have very few of course the return is gonna be higher but the risk is also gonna be much higher the quality you have a department which is highly prestigious which is into all these top ten classifications this is bound for historical reasons because women only enter higher education in the last twenty thirty years this is going to be dominated by men so if women don't like to work in fields which are male-dominated what you are going to find is that the the highly prestigious fields the fields which are more fashionable etc are going to be male-dominated they are not gonna be female dominated okay eventually what we also observe is that they if we look over time how this segregation by fill has been going on what will surface that despite the numbers being low for women in many of the fields they are changing women are entering newer fields why is it so well one possibility is that there is a congestion basically there are too many women working on labor and development etc so even if you want to compete with your female colleagues you may do it from a different field you may do it from econometrics or theory or whatever this is one possibility my interpretation of the dynamics of the historical evolution is that women started preferring certain fields because they were feeling in the wrong flesh the problem surrounding their mothers that are mothers etc so they started you look at women who finish the PhD in the 70s or etcetera they were starting to choose social fields a development education etc etc because these were the problems that they wanted to solve in this world this is what they really wanted to do as time goes by maybe some of these problems get somewhat solve or or they give up or whatever and the newer generation seem to be moving in in some other fields so for instance this is my let me just tell you couple of things about my sample the sample is the top 50 departments in the world nowadays so what we I did with my two co-authors was to go to the website I did take revolution allows us to have a lot of information so we went to the website and downloaded they were the Seavey's of all the members of these departments and therefore through there were websites and through the cities we could retrieve their history we knew where Marissa was 10 years ago well what other papers that he's writing on and we could allocate fields to two different people so for instance this I don't know you can see but health education and welfare the blue bar is the proportion of women among researches in that field so it's not the denominator is not women overall women is men and women we work in on health education on welfare and there you see that the proportion it's about 25% whereas in some other fields like mathematical quantitative financial it is much lower between 5 and 10% but in no field this proportion exceeds 8 6 50% why is it so well because as I said before the women are the access of women to the academic to the economics profession the academic profession is a new event this this graph for instance tells you which is the year in which they finish their PhD the doctorate in the current composition of Department so if I take it is suppose you're a department I take a snapshot a photograph of you and I count how many of you finish your PhD in the 70s how many in the 80s how many in the 90s you look at the red line these are men so this is like an equally distributed proportion so you had all men middle man mean and younger men almost in the same proportions but if you look at women this is a highly steep line so the blue line is women you have a lot of younger women women with a recent phd's in the department whereas all the women were negligible proportion there okay so for instance this is the proportion of women finishing pcs in in in recent times and in past times so the proportion of women finishing piece this decision in my top 50 universities is about 30 percent a little bit less 20 percent but the proportion of professors of tenured professors of people who are established there it's only about 10 percent so if if there is convergence in a few years we'll see 30 percent of female professors but if there is no discrimination or self selection or many of the other stories I told you so you know let me just say this is the an index of segregation so when it forms doubt means that men women are entering new fields they are less segregated if you look over time in the 70s in the 80s this going up going down the first the first two bars the gray and the blue bar I want explain what they mean but it's different ways of measuring segregation it's just a total segregation when it is zero means that the segregation is low when it is one this is an industry this between zero one it is very high so you see it is going down that is this a spread of women in in in other fields well the media say that the most of them most of the hypothesis that I told you before about size about quality of the field are not rejected by the data you test for this data with this data I have 2,000 people in mine out of which 300 are women and basically what you see is that the overall the the hypotheses are verified but over time they are changing women are entering this this new field you may think maybe the world is more competitive these days to become a profession you need more that what you became you need 20 years old maybe preferences are changing etc finally one thing that you could do is say once you have downloaded all this information from the website you could write to to this women and ask them they straight the question why are you working in these fields rather to infer that through some statistical procedure just ask them directly so we did that we wrote to way we had three handed in ours in our sample of course response rates are not a hundred percent so we got replies by a hundred and twenty five and we asked them about various things related to their choices for instance the family background whether they are kids these please remember my drive they are interesting you have kid or you have a sick relative or whatever this might raise your appetite for certain fields you may feel that it is unfair the way kids are treated in this world and you would become a development economist etc etc so we asked these people and we also asked men we had a lot of men in our sample so we did something with the statisticians do which is construct a match sample so it's a sample of people about the same age with did a piece this in the same years etc etc these are a small numbers I don't know you could see them but they what I just want to show is if you look we split the replies in sort of three groups so those who chose due to seeking economic or academic success okay I want to be rich I want to be famous in academics that was the reason I chose the field the second one is social interest I want to help the kids I want to help the poor people of the world etc then maybe because there is a lot of mobility among these departments you basically specialize in the fields in which your department is very strong so suppose you you go to the apartment which is extremely strong in econometrics and not so strong in macroeconomics then of course it would be silly just to do macro economics especially specialize of this don't peel of the of the department so if you look at the distribution what you see is that the among women fifty percent overall said I did they do it for social interests whereas men only do it twenty two percent but of course because we have the H in under inverted commas P we have the deal in which they finish their PhD which is a good good proxy for for H we can follow how this proportion has evolved over time which is the red column in the middle in the second in the second set of numbers so you see that for those women who finish before they in the before the mid-eighties like sixty percent of them were doing it for social interest whereas this has fallen to 33 percent nowadays so things seem to be changing right why are they changing I sort of a venture various explanations but now let me just jump a little bit forward and talk a little bit about non-academics what I want to argue is that the gender differences in the like this last five minutes may be due to a large extent to what economists call self-fulfilling prophecies that is the idea that beliefs drive results so let me just give you a very simple example suppose I'm going to where the heart of an employer I'm an employer I have two candidates um male candidate and a female candidate and I had to think they are equally talented has the same laude at the same grade equally equally skilled but I have to decide which one to train more or allocate to to to career with a higher promotion profile I will always believe that in case something happens at home some relative kill some kids get ill or whatever it will be the woman who has to leave the job on and go there if there are long hours unexpected long hours you have to stay until 11:00 the woman will have more difficult therefore I'll give more training this is what is called sort of a statistical discrimination I'll give more training to the man I'll pay the man more because it's correct end up be more productive this is what I think as an employee now let's go to the household Basu you have partnered you are in the household you are deciding who should devote more time to work at home and who should devote more time to work in the market what is going to drive my decision well basically the relative wage if the man earns more the opportunity cost what the column is called opportunity cost of staying at home is going to be higher for them okay so from the household viewpoint the distribution of tasks apart from some comparative advantage like breastfeeding or not many more and this is of course has been falling over time because the new methods of nurturing hits the less need for physical strength in mall jobs these days very few jobs really require physical strength make the decision to be tilted towards the women at home and the men at the market at the end both beliefs are fulfilled because the my the employer sees the woman working at home and therefore says what I did well that's why I I train more and I gave a more high-profile job to the man and at home the couple meets and say well you see it's better what we do because the woman will earn lower weights in the weight in the in the market so both both believes that totally fulfil the only way to break these beliefs is some imposition some rule of law that part I was talking about which is affirmative action or the right affirmative action has been typically criticized on the basis that is not equal opportunity if I am affirmed I want employees to bring revenue to be in profit to the firm and this is claimed to be gender neutral if the woman brings more I'll give the room the women more opportunities but this does not work as long as these beliefs are entrench in society you have to break them the same happens for instance with affirmative affirmative action and racial segregation that is you have to break these beliefs that the people of a different race are inferior in some sense or less reliable etc how do you do that by giving them the opportunity to prove that this is not the case there is always of course the criticism that they made disincentive 8 people from accumulating human capital if you get into the bay into Harbor because you are black and respectively of whether you have good grades or bad grades that is not going to work but of course we already know that for instance in the case of a gender discrimination women are the best students they are the overall majority in the university so if that these incentives are not going to take place at all one difference and with these are finished whereas in the case of racial discriminations when you break these believes it may take a long time you can lift the policy you can eliminate the policy and what from from that time from that point a ever employers will believe that blacks are as productive as as whites and of course because blacks know that they have the possibility of showing their employers that they are as good they will study more they will get perform better etc etc so it's a virtuous cycle but in the case of women you cannot lift these policies so why is it so because once you leave the policies once you eliminate say quotas for instance in my own country in Spain we have passed a recent law with a lot of criticism I must say but the Pascal's law where we force first with more than 250 employees to have at least 40% of the board members women and we the electoral lives we just had administrative elections municipality as and regional elections they're all the parties in even the smallest towns had to present at least at least with at least 40 percent of women there in fact they they were funny places because party percentage 100 women and that was not allowed and of course they had to present at least 40 percent of men but this is the way that is the way it is going to work and that cannot be lifted because once it is lifted of course there is a difference between whites and blacks and men and women is that men and women have households okay they have kids they live together they share certain duties whereas blacks and whites in principle they don't do that and of course they may be multiracial couples etc but once you leave these policies the believes the prejudices will raise again if the kids get sick the woman will go to they will be at home and the man will stay at at the job okay I think I'll stop here and thank you for your patience thank you thank you very much professor gelato what is very interesting presentation we have heard very interesting remarks underway women compete on research fields from men and women with the heard interesting issues and motivations professor Delano has mentioned segregation effects with her decreasing with the younger cohorts and has mentioned equal opportunity policies a lot has been mentioned so now you have the floor for questions and comments hey Jonah pyramid Amanda we have two questions so good thank you well I haven't got a question I would like to make few remarks and of course there are underlying questions I don't know where to start from because many interesting things have been said well you choose one well talking about professional segregation and gender-based aggregation and considering what Professor the Lada has said there's a sort of horizontal segregation and referring to the fields and then there's also vertical segregation and professor de la DOE has mentioned several reasons why this is the case he has emphasized competences but opportunities as well I am a retired teacher but have always considered this topic as extremely important and I have been discriminated and I got very very angry and I fought a lot I'm still fighting against this so considering my personal experience I think that this reflection should be extended in particular to the education and training world and this reflection should be started as early as possible the professor de la DOE has mentioned a culture of discrimination this is visible in our daily life if we consider our own life it is easy to see that there's a different focus on men versus women so we cannot forget that the education world does not take gender differences into consideration and I'm also referring to the learning path because very often you know the learning process is based on a male perspective even if we clearly know the scientific evidence that women are best students the justification which is often mentioned is that they are more diligent they work harder in the education world gender differences are not analyzed in depth and the difference in terms of results is not studied as to fill discrimination well in Spain there's a law establishing specific female chairs we also know that in some cases it is difficult for women to relate to men it is true that in our culture as women were not given the appropriate competence to exert power you and professor the ladder mentioned a very important issue women have decided to to be active in those fields where many things need to be corrected but I think that women have to be present also in those arenas where rules are decided I'm very glad and I would like to say this before concluding and very glad to see that there are many young people here and they think we've got to work with young people we'll get to work on equal opportunities I think that a younger women often believe they have perfect equal opportunities well is this the same in Spain are they really aware of what they are entitled have silica men to the party their gender started on their if I'm gonna definite the feminine invasion on so must say celebrity Donna ginger neva to do normal person so mrs. Coulter depute tournament a la paloma service an icky series found rather are there any other questions I'm glad to see that there are many questions in the beginning of your presentation you refer to the 15 85% to erasure and I think this race shown is seen in Italy Portugal and Spain if we go to Northern Europe Norway Finland Denmark man I'm not sure that this ratio is reversed but I think that there's a sort of 50/50 ratio well I'm not going to talk about the reasons why this is so but I would like to know what you think about this professor gelato you told us that growth in the process of developing female human capital but can this human capital become a social capital I mean can this capital be based on a network and therefore have a social impact thank you thank you very much for for these questions which are all very interesting the first speaker mentioned that I had referred my talk in fact two horizontal segregation so we are talking of across fields fields are more or less in principle important I mentioned you could qualify them in terms of quality okay it's like sports there are sports which raise more money and sports which raised less less money the vertical segregation issue is a women had a name for it which i think is very far it will be familiar which is a take glass ceilings so there is this ceiling that once you touch it it's intangible it's not written anywhere that is called class and then when you touch your head on it you cannot go through so for instance that's the reason why in most of the European countries including the Scandinavian ones and that goes to the third speaker the proportion of women in the boards of corporate firms etc is still very low in Scandinavia you'll have for instance sectors like the educational sector the health sector which are the proportion of women is more than 50% but then if you look at the school you'll have a I don't know 60% of women or if you look at the hospital you will have 60% of female doctors but then if you look who runs who who runs the the who assisted a schoolmaster who is the director of the hospital tends to be a man so the glass ceilings are very important in in Sweden in the Scandinavian Oh in their market cetera that has not disappeared they may have cut horizontal segregation horizontal differences but not vertical ones right of course the glasses in the story is a very interesting one because let's take again the assumption that the distribution of skills of talents is the same across genders then if women anticipate that they're gonna have a life harder harder life in reaching to the top those women that we see at the top those women who are very important work in the government who are in the in the boards of the of the corporation should be much better than men because if they come from the same distribution the cutoff point is going to be tougher for women therefore what we should see is that that those women do better than men they should get higher higher wages but that's not what we see so discrimination is not totally absent right but the one implication of these theories about what about the vertical segregation is that the women who are who reach it are much better because they had a harder life in enriching to the top there are also other issues which I realized with with I started my talk which base please relate to what degree of connection of link is there between house work and market work and wage salaried work well there is idea put up by some economists that they are substitute so if you were six hours or say twelve hours at home then you are tired to work for the for the market right so there is a substitution I think the results are quite a bit of evidence I that they may be complement run in a home is in a sense not too different from running a firm so they seem to be a lot of trades a lot of skills which are acquired and therefore for instance it is often the case that women in risk in positions of high responsibilities do better and the psychologists tell us this is because they had a family and they were running a family so a lot of solutions still have to be taken there I would be as abrupt as as possible by say well in the case of corporate firms as in in the top position she has imposed certain proportion of women this is not going to damage the firm's this is not going to damage their their their opportunities of profit or anything like that there are freedom of choice so this is somewhat related to the first dollar and and the third issue women are have been more active on gender issues as the second speaker yeah that is true that is in fact all these committees that I was mentioned at the beginning and that encouraged you to create in the Italian academia as well were just launched by by women who who fell discriminated and it's the same explanation as I said at the beginning of why they chose the topics that I was showing you I think they wanted to solve the problems that they were feeling in their own flesh but they of course this is an issue which I think a very exciting issue differ in so many things and apparently in so few things and I think it's good that they and a lot of men for instance say the most famous economic decomposition about gender differences due to two main Oaxaca and blinded convergence and social capital I think there is the view that the women are less prone to waste it weh-weh wasted competition men tend to be to compete too much they'd love competing but for the sake of it and in this sense if social norms is what we heard yesterday / persistent trust stable trust a firm rooted trust I think there is a much quite a lot to to win in having these women in leading positions and imposing them as soon as possible thank altar demand a rapid evolution qui passe mo conclude the realtor Carrillo Sita kid generate economies what kind of economists but in Italian general means both kind and gender this is the piece of information to conclude this session thank you very much for your contribution thank you very much professor the ladder for your very interesting presentation and I wish you a very controlled possible