cv.ahm {AHM} | R Documentation |

## This is one of the main functions. It perform the cross validation on ahm models to select the optimal setting of hyper parameter h

### Description

This is one of the main functions. It perform the cross validation on ahm models to select the optimal setting of hyper parameter h

### Usage

```
cv.ahm(y, x, powerh_path = NULL, metric = c("mse", "AICc"), num_major = 3,
dist_minor = c(2, 2, 1), type = "weak", alpha = 0, lambda_seq = seq(0,
5, 0.01), nfolds = NULL, mapping_type = c("power"), rep_gcv = 100)
```

### Arguments

`y` |
numeric vector |

`x` |
data.frame Note the column names of the x should be in the order of major components, minor components, and no interactions between major or minor components are needed. |

`powerh_path` |
if NULL, then the default is the vector: round(seq(0.001,2,length.out =15),3) |

`metric` |
"mse" or "AICc" the metric used in cross validtion where the minimum is selected as the optimal |

`num_major` |
number of major components |

`dist_minor` |
the allocation of number of minor components nested under major components |

`type` |
heredity type, weak heredity is the current support type |

`alpha` |
0 is for the ridge in glmnet https://web.stanford.edu/~hastie/glmnet/glmnet_alpha.html |

`lambda_seq` |
a numeric vector for the options of lambda used in ridge regression for estimating the initials |

`nfolds` |
used in cv.glmnet for initial value of parameters in the non-negative garrote method |

`mapping_type` |
the form of the coefficient function of major components in front of corresponding minor terms. Currently only support "power" |

`rep_gcv` |
the number of choices of tuning parameter used in the GCV selection |

### Value

Return a list

### Examples

```
data("pringles_fat")
data_fat = pringles_fat
h_tmp = 1.3
x = data_fat[,c("c1","c2","c3","x11","x12","x21","x22")]
y = data_fat[,1]
powerh_path = round(seq(0.001,2,length.out =15),3)
num_major = 3; dist_minor = c(2,2,1)
res = cv.ahm (y, x, powerh_path=powerh_path, metric = "mse", num_major, dist_minor, type = "weak"
, alpha=0, lambda_seq=seq(0,5,0.01), nfolds=NULL, mapping_type = c("power"), rep_gcv=100)
object = res$metric_mse
```

*AHM*version 1.0.1 Index]