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python – 将PyMC2代码移植到PyMC3 – 体育分析的分层模型

作者:互联网

我尝试了以下代码,但遇到了问题.
我认为.values是问题,但我如何将其编码为Theano对象?

以下是我的数据来源

home_team,away_team,home_score,away_score
Wales,Italy,23,15
France,England,26,24
Ireland,Scotland,28,6
Ireland,Wales,26,3
Scotland,England,0,20
France,Italy,30,10
Wales,France,27,6
Italy,Scotland,20,21
England,Ireland,13,10
Ireland,Italy,46,7
Scotland,France,17,19
England,Wales,29,18
Italy,England,11,52
Wales,Scotland,51,3
France,Ireland,20,22

以下是PyMC2代码:
    data_file = DATA_DIR’ results_2014.csv’

df = pd.read_csv(data_file, sep=',')
# Or whatever it takes to get this into a data frame.
teams = df.home_team.unique()
teams = pd.DataFrame(teams, columns=['team'])
teams['i'] = teams.index
df = pd.merge(df, teams, left_on='home_team', right_on='team', how='left')
df = df.rename(columns = {'i': 'i_home'}).drop('team', 1)
df = pd.merge(df, teams, left_on='away_team', right_on='team', how='left')
df = df.rename(columns = {'i': 'i_away'}).drop('team', 1)
observed_home_goals = df.home_score.values
observed_away_goals = df.away_score.values
home_team = df.i_home.values
away_team = df.i_away.values
num_teams = len(df.i_home.drop_duplicates())
num_games = len(home_team)
g = df.groupby('i_away')
att_starting_points = np.log(g.away_score.mean())
g = df.groupby('i_home')
def_starting_points = -np.log(g.away_score.mean())

#hyperpriors
home = pymc.Normal('home', 0, .0001, value=0)
tau_att = pymc.Gamma('tau_att', .1, .1, value=10)
tau_def = pymc.Gamma('tau_def', .1, .1, value=10)
intercept = pymc.Normal('intercept', 0, .0001, value=0)
#team-specific parameters
atts_star = pymc.Normal("atts_star", 
                        mu=0, 
                        tau=tau_att, 
                        size=num_teams, 
                        value=att_starting_points.values)
defs_star = pymc.Normal("defs_star", 
                        mu=0, 
                        tau=tau_def, 
                        size=num_teams, 
                        value=def_starting_points.values) 

# trick to code the sum to zero constraint
@pymc.deterministic
def atts(atts_star=atts_star):
    atts = atts_star.copy()
    atts = atts - np.mean(atts_star)
    return atts

@pymc.deterministic
def defs(defs_star=defs_star):
    defs = defs_star.copy()
    defs = defs - np.mean(defs_star)
    return defs

@pymc.deterministic
def home_theta(home_team=home_team, 
               away_team=away_team, 
               home=home, 
               atts=atts, 
               defs=defs, 
               intercept=intercept): 
    return np.exp(intercept + 
                  home + 
                  atts[home_team] + 
                  defs[away_team])

@pymc.deterministic
def away_theta(home_team=home_team, 
               away_team=away_team, 
               home=home, 
               atts=atts, 
               defs=defs, 
               intercept=intercept): 
    return np.exp(intercept + 
                  atts[away_team] + 
                  defs[home_team])   

home_points = pymc.Poisson('home_points', 
                          mu=home_theta, 
                          value=observed_home_goals, 
                          observed=True)
away_points = pymc.Poisson('away_points', 
                          mu=away_theta, 
                          value=observed_away_goals, 
                          observed=True)

mcmc = pymc.MCMC([home, intercept, tau_att, tau_def, 
                  home_theta, away_theta, 
                  atts_star, defs_star, atts, defs, 
                  home_points, away_points])
map_ = pymc.MAP( mcmc )
map_.fit()

mcmc.sample(200000, 40000, 20)

我尝试移植到PyMC3

标签:python,pymc,pymc3
来源: https://codeday.me/bug/20190528/1170152.html